Topic 1 · Particles and the three states of matter — the scripts
What you are deciding: go-ahead for video generation on this topic, card by card.
Out of scope: articles and PP100 items (not on this page).
Here: the intro video, 10 lesson videos (2 marked by the author as “could do without a video”) and the summary video, in teaching order. Each card: the script, the attached question, then the quiz the student meets after the video.
How: tap one button per card. Taps and notes save as you go and are sent; the Notes tab shows what has gone and re-sends.
Introduction: Particles and the three states of matter
Script
| Say | Screen |
|---|---|
| Here are a spoon, a glass of juice and a balloon of air. | [the spoon, the glass of juice and the balloon side by side] |
| The spoon keeps its shape wherever you put it. | [spoon moves cup to bowl] |
| The juice flows into any shape you pour it into. | [juice pours glass to bowl] |
| The air spreads out to fill whatever holds it. | [balloon inflates] |
| The spoon, the juice and the air behave in three different ways. | [labels appear: SOLID, LIQUID, GAS] |
| So why does the spoon hold its shape when the juice and the air cannot, and what are all three made of? | [question mark over the spoon, the juice and the balloon; a magnifier hovers, not yet zoomed] |
| To find out, we will look at what everything is made of, and why solids, liquids and gases behave as they do. | [the spoon, the juice and the balloon stay] |
| Okay, so are you ready to find out what a spoon, a glass of juice and a balloon of air are made of? | [the spoon, the juice and the balloon hold; the poll follows on the page] |
The ready line's poll — the attached item (no key; the intro teaches nothing)
Okay, so are you ready to find out what a spoon, a glass of juice and a balloon of air are made of?
- A Yes, let's go! — Great. Here we go.
- B Not sure yet — That's fine. We start small and take it one step at a time.
- C Let me watch that again — Good idea. Watch it again, then come back.
Answer
No key. A poll: every reply is accepted with its friendly line.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
What counts as matter
MAT-001 · What matter is — Decide whether something is matter or not by checking whether it has mass and takes up space.
Script
| Say | Screen |
|---|---|
| Here is a flat soccer ball on a balance. | [flat ball on a balance; readout 412 g] |
| The balance reads 412 grams. | [readout pulses] |
| A student pumps the ball up hard and puts it back. | [pump; ball rounds out; back on the pan] |
| Now the balance reads 417 grams. | [readout changes to 417 g] |
| The balance measures how much material is in the ball, and scientists call that amount its mass. | [chip: MASS] |
| Only air went in, so the air has mass, about 5 grams of it. | [label AIR on the ball; chip: HAS MASS] |
| And the pumped ball is bigger, so the air takes up space. | [chip: TAKES UP SPACE] |
| Anything that has mass and takes up space is called matter. | [chip: MATTER] |
| Air has mass and takes up space, so air is matter. | [tick beside MATTER] |
| Here are some more examples. | [four empty panels appear] |
| A stone has mass and takes up space, so a stone is matter. | [stone panel; tick] |
| Water has mass and takes up space, so water is matter. | [water panel; tick] |
| But now consider the light from a lamp. | [lamp shining on the empty pan; readout unchanged] |
| Light has no mass and takes up no space, so light is not matter. | [lamp panel; cross] |
| And a shadow has no mass and takes up no space, so a shadow is not matter. | [shadow panel; cross] |
| So, here's what we've seen. Matter is anything that has mass and takes up space. | [the rule slide: the flat ball and the pumped ball; chips HAS MASS, TAKES UP SPACE, MATTER; nothing else printed] |
| So the extra 5 grams on the balance was air, and air is matter. | [417 g readout] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: one line — “Matter is anything that has mass and takes up space.”] |
“Okay, now your turn.” — the attached question
A balance reads about 5 g more after a ball is pumped full of air. What does that show about air?
- A Air has mass.
- B Air has no mass.
Answer
Key: A — Air has mass.
The balance reads more.
So air has mass.
Feedback per option
- A Only air goes in, and the reading goes up.
- B The reading goes up, and only air went in. So air has mass.
Quiz after the video — the mastery check, 11 items
Which bag has more mass?
- A the flour
- B the sugar
- C they have the same mass
Answer
Key: A — the flour
The flour reads 1000 g and the sugar reads 500 g.
So the flour has more mass.
Feedback per option
- A A bigger balance reading means more mass.
- B A bigger balance reading means more mass, and the flour reads more.
- C The two bags read differently, so their masses differ.
A student pushes an empty cup upside down into a bowl of water. The inside of the cup stays dry. What fills the inside of the cup?
- A air
- B nothing
Answer
Key: A — air
Air takes up space, so the water cannot get in.
Feedback per option
- A Air fills the cup, so the water cannot get in.
- B Something keeps the water out. That something is air.
What do scientists call anything that has mass and takes up space?
Typed answer
Answer
Accepted: matter
What is matter?
- A anything that has mass and takes up space
- B anything you can see
- C anything that is solid
Answer
Key: A — anything that has mass and takes up space
Feedback per option
- A Matter is anything that has mass and takes up space.
- B Air is matter, and you cannot see it. Matter is anything that has mass and takes up space.
- C Water and air are matter too. Matter is anything that has mass and takes up space.
Steam rises from a kettle. Is steam matter?
- A yes
- B no
Answer
Key: A — yes
So steam is matter.
Feedback per option
- A Steam has mass and takes up space.
- B Steam has mass and takes up space, so steam is matter.
A glass of milk stands on a table. Is the milk matter?
- A yes
- B no
Answer
Key: A — yes
So milk is matter.
Feedback per option
- A Milk has mass and takes up space.
- B Milk has mass and takes up space, so milk is matter.
A drum is hit and makes a sound. Is the sound matter?
- A yes
- B no
Answer
Key: B — no
So a sound is not matter.
Feedback per option
- A A sound can be loud, but loud is not the same as heavy. A sound has no mass and takes up no space.
- B A sound has no mass and takes up no space, so a sound is not matter.
A radiator gives out heat. Is the heat matter?
- A yes
- B no
Answer
Key: B — no
So heat is not matter.
Feedback per option
- A Heat can be felt, but being felt is not the test. Heat has no mass and takes up no space.
- B Heat has no mass and takes up no space, so heat is not matter.
A balloon is filled with helium. Is the helium matter?
- A yes
- B no
Answer
Key: A — yes
So helium is matter.
Feedback per option
- A Helium has mass and takes up space.
- B Helium has mass and takes up space, so helium is matter.
A phone screen gives out light. Is the light matter?
- A yes
- B no
Answer
Key: B — no
So light is not matter.
Feedback per option
- A Light can be seen, but being seen is not the test. Light has no mass and takes up no space.
- B Light has no mass and takes up no space, so light is not matter.
Jamal says: "Air is not matter, because air weighs nothing." Is Jamal correct?
- A yes
- B no
Answer
Key: B — no
The pumped-up ball had about 5 g more mass than the flat ball.
Air also takes up space.
So air is matter.
Feedback per option
- A Air feels as if it has no mass, but a pumped-up ball reads more on the balance than the same ball flat. Air has mass.
- B Air has mass: a pumped-up ball has more mass than the same ball flat. Air also takes up space, so air is matter.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Matter is made of particles too small to see
MAT-002 · Matter is made of particles too small to see — State that all matter is made up of particles that cannot be seen.
Script
| Say | Screen |
|---|---|
| Here is a glass with 200 milliliters of water. | [glass of water; label 200 mL] |
| A student tips in 10 grams of sugar and stirs. | [sugar grains fall in; spoon stirs] |
| The grains shrink, and vanish. | [grains shrink to nothing] |
| The water looks clear. | [clear glass] |
| She sips the water, and the water tastes sweet. | [sip; chip: TASTES SWEET] |
| So the sugar is still there. | [chip: SUGAR STILL HERE] |
| Let's zoom in. | [magnifier circle grows over the water] |
| Where did the sugar go? | [question mark on the glass] |
| It broke into pieces far too small to see. | [dark circles appear among light circles] |
| And those pieces spread all through the water. | [dark circles drift apart through the light ones] |
| Scientists call these tiny pieces particles. | [chip: PARTICLES] |
| One particle is far too small to see, and far too small to taste. | [one dark circle isolated, then shrinks to a dot] |
| A grain of sugar you can see is billions of particles packed together. | [dot multiplies into a grain] |
| The water is made of particles too. | [light circles labelled: water particles] |
| And it is not only sugar and water. | [zoom out] |
| A stone is made of particles. | [stone; magnifier shows particles] |
| The air in a soccer ball is made of particles. | [ball; magnifier shows particles far apart] |
| So, here's what we've seen. All matter is made of particles that are far too small to see. | [the rule slide: the glass, the stone and the ball, each with its magnifier of particles; chip PARTICLES; nothing else printed] |
| The sugar is still in the glass, as billions of particles too small to see. | [clear glass with magnifier] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: one line — “All matter is made of particles that are far too small to see.”] |
“Okay, now your turn.” — the attached question
A student stirs sugar into water until nobody can see it, but the water tastes sweet. Where is the sugar?
- A It is in the water, as particles too small to see.
- B It is gone.
Answer
Key: A — It is in the water, as particles too small to see.
So the sugar is still there, as particles too small to see.
Feedback per option
- A The sugar broke into particles far too small to see.
- B The water tastes sweet, so the sugar is still there.
Quiz after the video — the mastery check, 8 items
Sugar has mass and takes up space. Is sugar matter?
- A yes
- B no
Answer
Key: A — yes
So sugar is matter.
Feedback per option
- A Sugar has mass and takes up space.
- B Sugar has mass and takes up space, so sugar is matter.
What do scientists call the tiny pieces that all matter is made of?
Typed answer
Answer
Accepted: particles · particle
What is a particle?
- A one of the tiny pieces all matter is made of, far too small to see
- B a grain you can see
- C a drop of water
Answer
Key: A — one of the tiny pieces all matter is made of, far too small to see
Scientists call these pieces particles.
Feedback per option
- A A particle is one of the tiny pieces all matter is made of.
- B A grain you can see is billions of particles packed together.
- C A drop of water is made of billions of particles.
True or false: a pencil is made of particles.
- A true
- B false
Answer
Key: A — true
All matter is made of particles.
So a pencil is made of particles.
Feedback per option
- A A pencil is matter, and all matter is made of particles.
- B A pencil looks like one solid piece, but every piece of matter is made of particles far too small to see.
True or false: you can see a single particle of salt with your eyes.
- A true
- B false
Answer
Key: B — false
A grain of salt you can see is billions of particles packed together.
Feedback per option
- A A grain of salt is visible, but one grain is billions of particles. A single particle is far too small to see.
- B A single particle is far too small to see.
True or false: the milk in a carton is made of particles.
- A true
- B false
Answer
Key: A — true
All matter is made of particles.
So the milk is made of particles.
Feedback per option
- A Milk is matter, and all matter is made of particles.
- B Milk looks smooth with no pieces in it, but every piece of matter is made of particles far too small to see.
A student drops a peppermint into a glass of water and leaves it until it has vanished. She sips the water and it tastes of mint. Explain why the water tastes of mint even though she cannot see any of the peppermint.
Starter: The water tastes of mint because…
Answer
Model answer · ['the peppermint is still in the water', 'the peppermint is in particles too small to see', 'the particles spread through the water'] points
The peppermint broke into particles far too small to see.
The peppermint particles spread through the water.
Salt is stirred into a pan of water and disappears. Maya says: "The salt has turned into water." Is Maya correct?
- A yes
- B no
Answer
Key: B — no
The salt broke into particles far too small to see.
The salt particles spread through the water.
Feedback per option
- A The salt seems to vanish, but it is still salt. It broke into particles too small to see and spread through the water.
- B The salt is still there, as salt particles too small to see, spread through the water.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Particles never stop moving
MAT-003 · Particles are always moving — Explain an observation (such as a smell spreading across a room) using the idea that particles are constantly in motion.
Script
| Say | Screen |
|---|---|
| Here are students in a quiet classroom, seen from above. The windows are shut, and no fan is running. | [room plan; students at desks; back row labelled; chips: WINDOWS SHUT, NO FAN] |
| The teacher opens a bottle of perfume at the front. | [bottle opens; a few dark particles appear at its neck] |
| Twenty seconds later, the back row can smell it, and nobody carried the smell to them. | [timer runs 0 to 20 s; back-row desks highlight] |
| So how did the perfume cross the room? | [question mark] |
| Its particles moved across by themselves. | [dark circles drift across the plan, faintly] |
| Perfume is matter, so perfume is made of particles. | [magnifier on the bottle neck: dark circles] |
| Some perfume particles leave the open bottle. | [dark circles drift out] |
| Particles are always moving. | [chip: ALWAYS MOVING; circles jiggle and travel] |
| The air is made of particles too, and they are moving. | [light circles fill the room, all moving] |
| The perfume particles bump into air particles. | [a dark circle hits a light one] |
| They bounce off and keep moving, in every direction. | [dark circles scatter in all directions] |
| So the perfume particles spread through the whole room. | [dark circles spread across the plan] |
| After twenty seconds, some reach the back row. | [dark circles at the back-row desks; timer at 20 s; chip: SMELL REACHES THE BACK ROW] |
| Now consider a glass of still water, with one drop of food coloring and no stirring. | [glass; drop falls in] |
| By the next morning the whole glass is colored. | [color spreads slowly through the glass; clock advances] |
| Particles never stop moving, so the coloring particles moved through the whole glass. | [magnifier: dark circles moving among light ones] |
| Particles are always moving. | [the rule slide: the room plan and the glass; chip ALWAYS MOVING; nothing else printed] |
| They never stop. | [the rule slide holds] |
| So in the classroom, moving perfume particles spread from the bottle to the back row. | [room plan at 20 s] |
| That is how the smell crossed a still room. | [back row highlighted] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: one line — “Particles are always moving. They never stop.”] |
“Okay, now your turn.” — the attached question
A perfume bottle is opened at the front of a still room, with the windows shut and no fan. The smell reaches the back row. What carries it?
- A A breeze.
- B Moving perfume particles.
Answer
Key: B — Moving perfume particles.
The perfume particles spread through the still room to the back row.
Feedback per option
- A There is no breeze. The perfume particles move on their own.
- B Particles are always moving, so the perfume particles spread through the room.
Quiz after the video — the mastery check, 9 items
Perfume is matter. Is perfume made of particles?
- A yes
- B no
Answer
Key: A — yes
All matter is made of particles too small to see.
Feedback per option
- A All matter is made of particles too small to see.
- B Perfume is matter, and all matter is made of particles.
A bottle of vinegar is opened in a still kitchen. What happens to the vinegar particles over the next minute?
- A They stay inside the bottle.
- B They spread out through the kitchen.
- C They sink to the floor.
Answer
Key: B — They spread out through the kitchen.
Particles are always moving.
So the vinegar particles spread out through the kitchen.
Feedback per option
- A Some particles leave the open bottle, and particles never stop moving.
- B Particles are always moving, so the vinegar particles spread out.
- C The particles move in every direction, not only down.
A pizza box is opened at one end of a quiet classroom. A minute later, a student at the other end smells the pizza. Explain how the smell reached her.
Starter: The smell reached her because…
Answer
Model answer · ['particles leave the pizza', 'particles are always moving', 'the particles spread across the classroom to her'] points
Particles are always moving.
The pizza particles bumped into air particles and kept moving in every direction.
They spread across the classroom until they reached her nose.
The air in a room feels completely still. Leo says: "The air particles are not moving." Is Leo correct?
- A yes
- B no
Answer
Key: B — no
The air feels still, but its particles are moving all the time.
Feedback per option
- A The air feels still, but its particles never stop moving. Still air is particles flying in every direction.
- B Air particles are always moving, even when the air feels completely still.
A match is blown out in a still room. A thin trail of smoke rises from it. What happens to the smoke over the next few minutes?
- A It stays as one thin trail.
- B It sinks to the floor.
- C It spreads through the room.
Answer
Key: C — It spreads through the room.
Particles are always moving.
So the smoke particles spread through the room.
Feedback per option
- A The smoke particles never stop moving, so the trail cannot stay as it is.
- B The particles move in every direction, not only down.
- C The smoke particles are always moving, so they spread through the room.
A bakery door is opened onto a still street. What happens to the smell of bread over the next minute?
- A It stays inside the bakery.
- B It spreads out along the street.
Answer
Key: B — It spreads out along the street.
Particles are always moving.
So they spread along the street.
Feedback per option
- A Some bread particles leave through the door, and particles never stop moving.
- B Particles are always moving, so the bread particles spread out.
A sugar cube sits in a glass of still water. Are the water particles around it moving?
- A yes
- B no
Answer
Key: A — yes
Feedback per option
- A Particles are always moving, even in still water.
- B The water looks still, but its particles never stop moving.
A lemon is cut in the kitchen. Ten minutes later the smell has reached the hallway. What moved?
- A lemon particles
- B the lemon itself
- C nothing
Answer
Key: A — lemon particles
Particles are always moving.
They spread through the air to the hallway.
Feedback per option
- A Lemon particles left the cut lemon and spread through the air.
- B The lemon stayed on the board. Its particles moved.
- C A smell reaches you when particles reach your nose.
True or false: the particles in a still puddle stop moving.
- A true
- B false
Answer
Key: B — false
Feedback per option
- A The puddle looks still, but its particles never stop moving.
- B Particles never stop moving, even in a still puddle.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Heating speeds particles up; cooling slows them down
MAT-004 · Heating speeds particles up; cooling slows them down — Predict how changing the temperature of a substance affects the speed of its particles.
Script
| Say | Screen |
|---|---|
| Here are two mugs, each with 250 milliliters of water. | [two mugs; labels 250 mL] |
| This one is at 10 degrees Celsius, and this one is at 80 degrees Celsius. | [labels 10 °C and 80 °C appear on the words] |
| A student drops a tea bag into each, and does not stir. | [two tea bags drop in] |
| After thirty seconds, the hot water is brown all the way through. | [timer runs; hot mug fully brown] |
| The cold water shows only a faint cloud around the bag. | [cold mug: faint cloud] |
| The tea and the water are the same in both mugs, so what is different about the hot water? | [question mark between the mugs] |
| Its particles move faster. | [chip on the hot mug: FASTER PARTICLES] |
| Let's zoom into the water. | [two particle boxes appear below the mugs] |
| Water is made of particles, and particles are always moving. | [particles jiggle in both boxes] |
| Heating a substance makes its particles move faster. | [80 °C box: long arrows; chip: HIGHER TEMPERATURE, FASTER PARTICLES] |
| Cooling makes them move more slowly. | [10 °C box: short arrows] |
| Tea particles leave the bag and bump into the moving water particles. | [dark tea particles enter each box] |
| Faster water particles knock the tea particles around faster. | [dark particles scatter quickly in the hot box, slowly in the cold] |
| So the brown color spreads through the hot mug sooner. | [hot mug brown; chip: COLOR SPREADS SOONER] |
| The particles do not grow or shrink; only their speed changes. | [both boxes: particles same size; chip: ONLY THE SPEED CHANGES] |
| So, heating makes particles move faster. Cooling makes them move more slowly. | [the rule slide: the two particle boxes, long arrows at 80 °C and short arrows at 10 °C; chips HEATING: FASTER, COOLING: SLOWER; nothing else printed] |
| So in the two mugs, the tea and the water were the same. | [two mugs] |
| Heating only made the hot water's particles move faster, so the color spread sooner. | [hot mug brown] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • Heating makes particles move faster. • Cooling makes them move more slowly.] |
“Okay, now your turn.” — the attached question
Two mugs hold water, one at 10 °C and one at 80 °C. In which mug are the water particles moving faster?
- A the 10 °C mug
- B the 80 °C mug
Answer
Key: B — the 80 °C mug
The 80 °C water's particles move faster.
Feedback per option
- A Cooler water has slower particles.
- B Heating makes particles move faster.
Quiz after the video — the mastery check, 9 items
A glass of water stands still on a table. Are its water particles moving?
- A yes
- B no
Answer
Key: A — yes
The water looks still, but its particles are moving all the time.
Feedback per option
- A Particles are always moving, even in water that stands still.
- B The water stands still, but its particles never stop moving.
A pan of soup is heated from 20 °C to 60 °C. What happens to the speed of its particles?
- A They move more slowly.
- B They move faster.
- C Their speed does not change.
Answer
Key: B — They move faster.
The soup is heated, so its particles move faster.
Feedback per option
- A Heating makes particles move faster, not more slowly.
- B Heating makes particles move faster.
- C Heating changes the speed of the particles.
Two drops of blue dye fall into two glasses of still water, one at 5 °C and one at 70 °C. The dye spreads through the 70 °C water much sooner. Explain why.
Starter: The dye spreads sooner in the 70 °C water because…
Answer
Model answer · ["the hotter water's particles move faster", 'heating makes particles move faster', 'faster water particles spread the dye particles sooner'] points
Heating makes particles move faster.
The faster water particles knock the dye particles around faster.
So the dye spreads through the whole glass sooner.
A metal rod is heated. Priya says: "The heat makes each particle in the rod bigger." Is Priya correct?
- A yes
- B no
Answer
Key: B — no
Heating makes them move faster.
Only their speed changes.
Feedback per option
- A A hot rod feels different, but its particles stay the same size. Heating makes the particles move faster.
- B Heating leaves each particle the same size and makes it move faster.
A glass of lemonade is cooled from 25 °C to 5 °C in a fridge. What happens to its particles?
- A They move faster.
- B They stop moving.
- C They move more slowly.
Answer
Key: C — They move more slowly.
The lemonade is cooled, so its particles move more slowly.
Feedback per option
- A Cooling slows particles down; heating speeds them up.
- B Particles never stop moving. Cooling only slows them down.
- C Cooling makes particles move more slowly.
Two identical cups of water: one at 15 °C, one at 75 °C. In which cup do the particles move faster?
- A the 15 °C cup
- B the 75 °C cup
Answer
Key: B — the 75 °C cup
The 75 °C water's particles move faster.
Feedback per option
- A Cooler water has slower particles.
- B A higher temperature means faster particles.
A pot of milk is warmed from 10 °C to 50 °C. What happens to the size of its particles?
- A They stay the same size.
- B They get bigger.
- C They get smaller.
Answer
Key: A — They stay the same size.
Their size does not change.
Feedback per option
- A Heating changes the speed of the particles, not their size.
- B Particles do not grow when heated.
- C Particles do not shrink when heated.
Two glasses of water look the same. In one, a drop of dye spreads in 20 seconds; in the other, in 3 minutes. Which glass is warmer?
- A the 20-second glass
- B the 3-minute glass
Answer
Key: A — the 20-second glass
Faster particles mean a higher temperature.
So the 20-second glass is warmer.
Feedback per option
- A Faster spreading means faster water particles, which means a higher temperature.
- B Slower spreading means slower particles, which means cooler water.
True or false: cooling a drink makes its particles move more slowly.
- A true
- B false
Answer
Key: A — true
Feedback per option
- A Cooling slows particles down.
- B A cold drink's particles still move, but cooling makes them move more slowly.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Solid, liquid or gas?
MAT-016 · Solid, liquid or gas — tell them apart — Classify a sample as a solid, a liquid or a gas from whether it keeps its own shape and whether it keeps its own volume.
Script
| Say | Screen |
|---|---|
| Here is a student pouring dry sand into a jar. It takes the jar's shape, just as water would. | [a student pours sand; it piles to the jar's shape; water pours into a second jar] |
| She says sand is a liquid, because it pours. | [the student beside the two jars] |
| We ask two questions: does it keep its own shape, and does it keep its own volume? | [chips: KEEPS ITS SHAPE? KEEPS ITS VOLUME?] |
| A steel spoon keeps its shape and volume in a cup, a bowl and a pitcher, so it is a solid. | [spoon moves container to container, unchanged; two ticks; label SOLID] |
| Here is 250 milliliters of juice. | [juice in a tall glass; label 250 mL] |
| In the glass it stands tall; in a wide bowl it lies flat. | [juice pours glass to bowl] |
| A measuring cup still reads 250 milliliters. | [measuring cup reads 250 mL] |
| It takes its container's shape but keeps its volume, so the juice is a liquid. | [cross on shape, tick on volume; label LIQUID] |
| Here is 20 milliliters of air sealed in a syringe. | [syringe at 20 mL] |
| She pulls the plunger out, and the air fills 60 milliliters. | [plunger out to 60 mL] |
| She pushes it in, and the same air fits into 10 milliliters. | [plunger in to 10 mL] |
| It keeps neither shape nor volume, so air is a gas. | [two crosses; label GAS] |
| Honey flows slowly, but it takes its jar's shape and keeps its volume, so honey is a liquid. | [honey pours; cross, tick; label LIQUID] |
| Back at the sand, one grain keeps its own shape and volume, so it is a solid. | [the jar of sand; zoom to a single grain; two ticks; label SOLID] |
| A jar of sand is thousands of tiny solids. | [zoom out to the jar] |
| So, here's what we've seen. | [the rule slide: the spoon, the juice and the syringe; nothing else printed] |
| A solid keeps its own shape and its own volume. | [the spoon; two ticks] |
| A liquid keeps its own volume but takes the shape of its container. | [the juice; cross, tick] |
| A gas keeps neither: it spreads to fill whatever space it is given. | [the syringe; two crosses] |
| So, when she said sand is a liquid, she was not right. Sand is a solid, in very small pieces. | [the jar of sand; label SOLID] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • A solid keeps its own shape and its own volume. • A liquid keeps its volume but takes the shape of its container. • A gas keeps neither: it fills whatever space it is given.] |
“Okay, now your turn.” — the attached question
Dry sand pours into a jar and takes the jar's shape. Is sand a liquid or a solid?
- A Sand is a liquid, because it flows.
- B Sand is a solid, because each grain keeps its shape and volume.
Answer
Key: B — Sand is a solid, because each grain keeps its shape and volume.
So sand is a solid, in very small pieces.
Feedback per option
- A Look at one grain: it keeps its own shape and its own volume.
- B Each grain is a tiny solid.
Quiz after the video — the mastery check, 11 items
A wooden block is moved from a box into a bag. What happens to its shape?
- A It stays the same.
- B It takes the shape of the bag.
Answer
Key: A — It stays the same.
Feedback per option
- A A wooden block keeps its own shape wherever you put it.
- B A bag is soft, but a solid does not take its container's shape. The block keeps its own shape in the bag.
Air, which is a gas, is blown into a balloon. Where does the air go?
- A It sits at the bottom of the balloon.
- B It spreads to fill the whole balloon.
Answer
Key: B — It spreads to fill the whole balloon.
Feedback per option
- A A gas spreads to fill all the space it is given, not just the bottom.
- B A gas spreads to fill all the space it is given.
A brick keeps its shape and its volume on any surface. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: A — solid
So the brick is a solid.
Feedback per option
- A It keeps its shape and its volume.
- B A liquid would take the shape of its container.
- C A gas would spread out.
Milk poured from a carton into a bowl takes the bowl's shape and stays 500 mL. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: B — liquid
So the milk is a liquid.
Feedback per option
- A A solid would keep its own shape.
- B It takes the container's shape but keeps its volume.
- C A gas would not keep its volume.
The air in a bicycle pump is squeezed into half the space. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
So the air is a gas.
Feedback per option
- A A solid keeps its volume.
- B A liquid keeps its volume.
- C It does not keep its volume.
An ice cube keeps its shape and volume in a glass, a bowl or a hand. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: A — solid
So the ice cube is a solid.
Feedback per option
- A It keeps its shape and its volume.
- B A liquid would take the container's shape.
- C A gas would spread out.
Cooking oil spreads flat across a pan but stays 50 mL. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: B — liquid
So the oil is a liquid.
Feedback per option
- A A solid keeps its own shape.
- B It takes the pan's shape but keeps its volume.
- C A gas would not keep its volume.
Helium from a small cylinder spreads out to fill a whole empty tank. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
It keeps neither shape nor volume.
So the helium is a gas.
Feedback per option
- A A solid keeps its shape and volume.
- B A liquid keeps its volume.
- C It spreads to fill whatever space it is given.
A coin keeps its shape and volume in a pocket or a purse. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: A — solid
So the coin is a solid.
Feedback per option
- A It keeps its shape and its volume.
- B A liquid would take the container's shape.
- C A gas would spread out.
Oxygen from a small hospital cylinder spreads out to fill a whole empty tank. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
It keeps neither shape nor volume.
So oxygen is a gas.
Feedback per option
- A A solid keeps its shape and volume.
- B A liquid keeps its volume.
- C It spreads to fill whatever space it is given.
Priya pours dry rice into a bowl. The rice takes the shape of the bowl. Priya says: "Rice is a liquid." Is Priya correct?
- A yes
- B no
Answer
Key: B — no
So each grain is a solid.
A bowl of rice is many tiny solids sliding over one another.
Feedback per option
- A A bowl of rice takes the bowl's shape, but each grain keeps its own shape. Rice is many tiny solids.
- B Each grain of rice keeps its own shape and volume, so rice is many tiny solids.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Why a solid keeps its shape
MAT-016b · Solid — explain it — Explain why a solid holds its shape by describing how its particles are arranged and how they move.
Script
| Say | Screen |
|---|---|
| Here is a steel spoon in a cup. | [spoon in cup] |
| Now the spoon goes into a bowl, then into a pitcher. | [spoon moves; shape unchanged] |
| It stays spoon-shaped every time. | [chip: KEEPS ITS SHAPE] |
| Water poured into the same three containers takes three different shapes. | [water pours into each] |
| So what holds the spoon in one shape? | [question mark on the spoon] |
| The particles inside it do, so let's zoom into the steel. | [magnifier grows into the particle box] |
| In a solid the particles are packed tightly, touching, in fixed positions. | [16 touching circles in rows; chips: TOUCHING, FIXED POSITIONS] |
| Particles are always moving, and each particle here vibrates on the spot. | [all circles jiggle in place; chip: VIBRATES ON THE SPOT] |
| Each one stays in its place. | [highlighted circle shakes, never leaves its cell] |
| No particle can move past its neighbors. | [a circle tries to slide, is blocked, springs back] |
| So the particles keep the same arrangement wherever the spoon goes. | [box travels cup to bowl to pitcher, arrangement unchanged] |
| The whole spoon holds one shape, and one volume. | [chips: ONE SHAPE, ONE VOLUME] |
| Now consider an ice cube dropped into a glass of juice. | [ice cube drops into juice] |
| Ice is a solid. | [magnifier on the cube: the same particle box] |
| Its particles cannot move past their neighbors. | [a circle blocked] |
| So the cube keeps its shape. | [cube floats, unchanged] |
| So, in a solid the particles are packed tightly, touching, in fixed positions. Each particle vibrates on the spot. | [the rule slide: the spoon and the particle box; chips TOUCHING, FIXED POSITIONS, VIBRATES ON THE SPOT; nothing else printed] |
| That is why a solid keeps its shape and its volume. | [spoon] |
| So the spoon's particles cannot move past one another, and it stays spoon-shaped in the cup, the bowl and the pitcher. | [spoon in the three containers] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • In a solid the particles are packed tightly, touching, in fixed positions. • Each particle vibrates on the spot. • That is why a solid keeps its shape and its volume.] |
“Okay, now your turn.” — the attached question
In a solid, what does each particle do?
- A It vibrates on the spot.
- B It slides past its neighbors.
- C It flies in every direction.
Answer
Key: A — It vibrates on the spot.
Each particle vibrates on the spot.
Feedback per option
- A The particles are in fixed positions and vibrate on the spot.
- B That is a liquid.
- C That is a gas.
Quiz after the video — the mastery check, 9 items
A glass marble keeps its shape and its volume in any container. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: A — solid
So the marble is a solid.
Feedback per option
- A It keeps its shape and its volume.
- B A liquid takes its container's shape.
- C A gas spreads out.
How are the particles in a solid arranged?
- A touching, with no fixed positions
- B touching, in fixed positions
- C far apart, with empty space between them
Answer
Key: B — touching, in fixed positions
Feedback per option
- A That is a liquid. In a solid the particles have fixed positions.
- B In a solid the particles are packed tightly, touching, in fixed positions.
- C That is a gas. In a solid the particles are touching.
A brick is lifted from a table and put in a bucket. It stays brick-shaped. Explain why the brick keeps its shape.
Starter: The brick keeps its shape because…
Answer
Model answer · ['the particles are touching, in fixed positions', 'each particle vibrates on the spot (it does not move away)', 'no particle can move past its neighbors, so the shape holds'] points
In a solid the particles are packed tightly, touching, in fixed positions.
Each particle vibrates on the spot.
No particle can move past its neighbors.
So the whole brick holds one shape.
Ava says: "The particles in a block of wood do not move at all." Is Ava correct?
- A yes
- B no
Answer
Key: B — no
In a solid each particle vibrates on the spot.
It shakes back and forth but stays in its place.
Feedback per option
- A A block of wood looks still, but its particles vibrate on the spot. Particles never stop moving.
- B The particles in a solid vibrate on the spot; they never stop moving.
A stone lies on a path. Which statement about its particles is correct?
- A They slide past one another.
- B They fly around inside the stone.
- C They vibrate on the spot.
Answer
Key: C — They vibrate on the spot.
In a solid the particles are in fixed positions, and each particle vibrates on the spot.
Feedback per option
- A That is a liquid. A stone is a solid.
- B That is a gas. A stone is a solid.
- C A stone is a solid, so its particles vibrate on the spot.
A coin lies on a table. How are its particles arranged?
- A far apart
- B touching, in fixed positions
- C touching, sliding past one another
Answer
Key: B — touching, in fixed positions
In a solid the particles are packed tightly, touching, in fixed positions.
Feedback per option
- A That is a gas.
- B A coin is a solid: touching, in fixed positions.
- C That is a liquid.
True or false: the particles in a rock are completely still.
- A true
- B false
Answer
Key: B — false
Feedback per option
- A A rock looks completely still, but each of its particles vibrates on the spot.
- B Each particle in a rock vibrates on the spot.
Why does a metal key keep its shape in your pocket?
- A Its particles cannot move past their neighbors.
- B Its particles are far apart.
- C Its particles slide past one another.
Answer
Key: A — Its particles cannot move past their neighbors.
No particle can move past its neighbors.
So the key holds one shape.
Feedback per option
- A Fixed positions, so the shape holds.
- B That is a gas.
- C That is a liquid.
A wooden ruler is a solid. What does each of its particles do?
- A It flies in every direction.
- B It slides past its neighbors.
- C It vibrates on the spot.
Answer
Key: C — It vibrates on the spot.
Each particle vibrates on the spot.
Feedback per option
- A That is a gas.
- B That is a liquid.
- C In a solid each particle vibrates on the spot.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Why a liquid takes the shape of its container
MAT-017b · Liquid — explain it — Explain why a liquid takes the shape of its container by describing how its particles are arranged and how they move.
Script
| Say | Screen |
|---|---|
| Here is 250 milliliters of juice, poured from a tall glass into a wide bowl. | [pour; juice flattens; label 250 mL] |
| The juice flows and flattens, but a steel spoon in the bowl keeps its shape. | [juice settles; spoon beside it, unchanged] |
| So why can the juice change shape while its volume stays 250 milliliters? | [question mark; label 250 mL on the bowl] |
| Its particles can slide. Let's zoom in, with a box of the spoon's particles on the left to compare. | [left: a box of touching particles in rows, labelled SOLID; right: the juice's particle box, labelled LIQUID] |
| In a liquid the particles still touch. | [chip on the liquid box: TOUCHING] |
| But they have no fixed positions. | [chip: NO FIXED POSITIONS; particles jumbled] |
| The particles slide past one another. | [one particle slides along a row; chip: SLIDE PAST] |
| When the juice pours into the bowl, the sliding particles rearrange to match the bowl's shape. | [box tilts and widens; particles slide to fill the new shape] |
| So the liquid takes the shape of its container. | [chip: TAKES THE CONTAINER'S SHAPE] |
| But the particles stay touching, so the juice takes up the same space as before. | [zoom: particles still touching; label 250 mL stays] |
| So the liquid keeps its volume. | [chip: KEEPS ITS VOLUME] |
| Now consider honey poured slowly into a jar. | [honey pours slowly] |
| Its particles slide past one another too, so the honey takes the jar's shape. | [magnifier: liquid box; honey fills the jar's shape] |
| So, in a liquid the particles touch but have no fixed positions. They slide past one another. | [the rule slide: the juice and the liquid box; chips TOUCHING, NO FIXED POSITIONS, SLIDE PAST; nothing else printed] |
| That is why a liquid takes the shape of its container but keeps its volume. | [bowl, 250 mL] |
| So the juice's sliding particles rearranged to fit the bowl and stayed touching. | [bowl; zoom on touching particles; label 250 mL] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • In a liquid the particles touch but have no fixed positions. • They slide past one another. • A liquid takes the shape of its container but keeps its volume.] |
“Okay, now your turn.” — the attached question
In a liquid, what do the particles do?
- A They touch and slide past one another.
- B They are far apart and fly.
Answer
Key: A — They touch and slide past one another.
They slide past one another.
Feedback per option
- A That is why a liquid flows but keeps its volume.
- B That is a gas. In a liquid the particles touch.
Quiz after the video — the mastery check, 7 items
Soup poured from a pan into a bowl takes the bowl's shape but keeps its volume. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: B — liquid
So the soup is a liquid.
Feedback per option
- A A solid keeps its own shape.
- B It takes the container's shape but keeps its volume.
- C A gas does not keep its volume.
In a solid, how do the particles move?
- A They slide past one another.
- B They fly in every direction.
- C Each particle vibrates on the spot.
Answer
Key: C — Each particle vibrates on the spot.
Feedback per option
- A That is a liquid.
- B That is a gas.
- C In a solid each particle vibrates on the spot.
How are the particles in a liquid arranged?
- A touching, in fixed positions
- B far apart, with empty space between them
- C touching, with no fixed positions
Answer
Key: C — touching, with no fixed positions
They slide past one another.
Feedback per option
- A That is a solid. In a liquid the particles have no fixed positions.
- B That is a gas. In a liquid the particles touch.
- C In a liquid the particles touch but have no fixed positions.
Milk is poured from a carton into a glass. The milk takes the shape of the glass. Explain why.
Starter: The milk takes the shape of the glass because…
Answer
Model answer · ['the particles have no fixed positions', 'the particles slide past one another', 'the sliding particles rearrange to fit the glass'] points
In a liquid the particles touch but have no fixed positions.
The particles slide past one another.
The sliding particles rearrange until the milk matches the shape of the glass.
Why does a liquid keep the same volume when it is poured into a different container?
- A Its particles spread far apart.
- B Its particles are in fixed positions.
- C Its particles stay touching.
Answer
Key: C — Its particles stay touching.
They do not spread apart.
So the liquid takes up the same space in any container.
Feedback per option
- A If the particles spread apart, the volume would grow. In a liquid they stay touching.
- B That is a solid. A liquid's particles slide, but they stay touching.
- C The particles stay touching, so the liquid takes up the same space.
Noah says: "A liquid can flow because its particles are far apart." Is Noah correct?
- A yes
- B no
Answer
Key: B — no
They have no fixed positions, so they slide past one another.
That is why a liquid flows.
Feedback per option
- A In a liquid the particles touch. Particles that are far apart make a gas, not a liquid. A liquid flows because its particles slide past one another.
- B In a liquid the particles touch. They flow because they slide past one another.
Melted chocolate is poured slowly into a mold and takes the mold's shape. Which statement about the chocolate's particles is correct?
- A They are in fixed positions.
- B They touch and slide past one another.
- C They are far apart and fly in every direction.
Answer
Key: B — They touch and slide past one another.
Its particles touch but have no fixed positions, and they slide past one another.
Feedback per option
- A That is a solid. The chocolate flows, so its particles are not fixed.
- B Melted chocolate is a liquid, so its particles touch and slide past one another.
- C That is a gas. The chocolate keeps its volume, so its particles touch.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Why a gas fills any container
MAT-018b · Gas — explain it — Explain why a gas fills any container by describing how its particles are arranged and how they move.
Script
| Say | Screen |
|---|---|
| Here is a sealed syringe with 20 milliliters of air. | [syringe at 20 mL] |
| A student pulls the plunger out, and the air fills 60 milliliters. | [plunger out to 60 mL] |
| She pushes it in, and the same air fits into 10 milliliters. | [plunger in to 10 mL] |
| How did the same air fit into less space? | [question mark] |
| Its particles moved closer together. Let's zoom in. | [magnifier grows into the gas box] |
| In a gas the particles are far apart, with empty space between them. | [chip: FAR APART; the gaps highlighted] |
| That space is truly empty: nothing is between the particles, not even air. | [chip: EMPTY SPACE; gap highlighted, blank] |
| The particles fly fast in every direction. | [particles shoot across the box; chip: FLY FAST] |
| Nothing holds them together, so they keep going until they hit a wall. | [particles bounce off the box walls] |
| Now let's watch six air particles in the syringe. | [syringe barrel with 6 particles] |
| She pulls the plunger out, and the same six spread through the bigger space. | [plunger out; particles spread to fill 60 mL] |
| She pushes it in, and the same six crowd into the smaller space. | [plunger in; particles crowd into 10 mL] |
| The particles stay the same size; only the empty space between them grows or shrinks. | [two barrels side by side; chip: SAME SIZE] |
| So, in a gas the particles are far apart with empty space between them. They fly fast in every direction. | [the rule slide: the syringe and the gas box; chips FAR APART, EMPTY SPACE, FLY FAST; nothing else printed] |
| That is why a gas fills any container it is given. | [syringe at 60 mL] |
| So in the syringe, the same particles spread into 60 milliliters and crowded into 10 milliliters. | [the two barrels; chip: SAME PARTICLES, DIFFERENT SPACE] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • Gas particles are far apart, with empty space between them. • They fly fast in every direction. • That is why a gas fills any container it is given.] |
“Okay, now your turn.” — the attached question
A student pushes in the plunger of a syringe full of air. What happens to the air particles?
- A They move closer together.
- B They get smaller.
Answer
Key: A — They move closer together.
Only the empty space between them shrinks.
Feedback per option
- A The same particles crowd into the smaller space.
- B Particles do not shrink. They move closer together.
Quiz after the video — the mastery check, 10 items
The air in a sealed plastic bottle can be squashed into half its space. Solid, liquid or gas?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
So the air is a gas.
Feedback per option
- A A solid keeps its volume.
- B A liquid keeps its volume.
- C It does not keep its volume.
In a liquid, how are the particles arranged?
- A far apart, with empty space between them
- B touching, with no fixed positions
- C touching, in fixed positions
Answer
Key: B — touching, with no fixed positions
Feedback per option
- A That is a gas.
- B In a liquid the particles touch but have no fixed positions.
- C That is a solid.
How are the particles in a gas arranged?
- A touching, in fixed positions
- B touching, with no fixed positions
- C far apart, with empty space between them
Answer
Key: C — far apart, with empty space between them
They fly fast in every direction.
Feedback per option
- A That is a solid. In a gas the particles are far apart.
- B That is a liquid. In a gas the particles are far apart.
- C In a gas the particles are far apart, with empty space between them.
A little air is let out of a bicycle tire into an empty, sealed bottle. The air spreads out to fill the whole bottle. Explain why.
Starter: The air fills the whole bottle because…
Answer
Model answer · ['the particles are far apart with empty space between them', 'the particles fly fast in every direction', 'nothing holds them together, so they reach every wall'] points
In a gas the particles are far apart, with empty space between them.
The particles fly fast in every direction.
Nothing holds them together, so they keep going until they hit the walls of the bottle.
A balloon is blown up. Zoe says: "The air particles inside grew bigger to fill the balloon." Is Zoe correct?
- A yes
- B no
Answer
Key: B — no
The particles fly apart.
So the empty space between them grows.
That is how the gas fills the bigger space.
Feedback per option
- A The balloon grows, but the particles do not. They stay the same size and spread out, with more empty space between them.
- B The particles stay the same size and spread out, so there is more empty space between them.
A sealed plastic bottle full of air can be squashed. The same bottle full of water cannot. Why can the air be squeezed?
- A The air particles are smaller than the water particles.
- B There is empty space between the air particles for them to move into.
- C The air particles are softer than the water particles.
Answer
Key: B — There is empty space between the air particles for them to move into.
Squashing the bottle moves the particles into that space.
In a liquid the particles are already touching, so there is no space to push them into.
Feedback per option
- A The size of the particles is not the reason. The air particles have empty space between them to move into.
- B Squashing the bottle moves the air particles into the empty space between them. Water particles are already touching.
- C Particles do not squash. The air particles have empty space between them to move into.
A little perfume gas is released into an empty sealed box. Where do its particles go?
- A They fill the whole box.
- B They sink to the bottom.
- C They stay in one corner.
Answer
Key: A — They fill the whole box.
Nothing holds them together, so they reach every wall.
Feedback per option
- A Gas particles fly in every direction until they hit the walls.
- B Gas particles fly in every direction, not only down.
- C Nothing holds gas particles together.
True or false: the space between gas particles is filled with air.
- A true
- B false
Answer
Key: B — false
Feedback per option
- A Air is itself gas particles, so it cannot fill the gaps between them. The space between gas particles is empty.
- B The space between gas particles is empty; nothing is there, not even air.
A foot pump squashes air into a smaller space. What changed about the air particles?
- A They are closer together.
- B They are smaller.
- C There are fewer of them.
Answer
Key: A — They are closer together.
Only the empty space between them shrank.
Feedback per option
- A The same particles crowd into the smaller space.
- B Particles do not shrink.
- C No particle left the pump.
How are the particles in a gas arranged?
- A touching, in fixed positions
- B touching, sliding
- C far apart, with empty space between them
Answer
Key: C — far apart, with empty space between them
Feedback per option
- A That is a solid.
- B That is a liquid.
- C In a gas the particles are far apart.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Rank the states by kinetic energy
MAT-019 · Order the states by kinetic energy — Order solid, liquid, and gas from least to most kinetic energy of their particles.
Script
| Say | Screen |
|---|---|
| Here are three particle boxes: ice, water and steam. | [three boxes; labels] |
| Ice, liquid water and steam are all water, so all three boxes hold the same water particles. | [chip: SAME PARTICLES] |
| In the ice, each particle vibrates on the spot. | [solid box jiggles] |
| In the water, the particles slide past one another. | [liquid box slides] |
| In the steam, the particles fly fast in every direction. | [gas box: particles shoot and bounce] |
| Which particles carry the most energy of movement? | [question mark] |
| The steam particles do. | [gas box highlighted] |
| A moving particle has energy because it is moving. | [one flying particle highlighted] |
| Energy of movement is called kinetic energy. | [chip: KINETIC ENERGY = ENERGY OF MOVEMENT] |
| The faster a particle moves, the more kinetic energy it has. | [short arrow, then long arrow; bar grows] |
| Gas particles fly fastest, so they have the most kinetic energy. | [gas box: bar MOST] |
| Liquid particles slide, so they have less. | [liquid box: bar shorter] |
| Solid particles only vibrate on the spot, so they have the least. | [solid box: bar shortest, LEAST] |
| From least to most kinetic energy, the order is solid, liquid, gas. | [the three bars line up in order] |
| The same order holds for any substance, like wax. | [labels change to solid wax, liquid wax, wax vapor; bars unchanged] |
| Energy of movement is called kinetic energy. | [the rule slide: the three boxes with their bars; chip KINETIC ENERGY; nothing else printed] |
| Solid, liquid and gas run from least to most kinetic energy. | [the bars labelled LEAST to MOST] |
| So the flying steam particles carry the most kinetic energy, and the vibrating ice particles carry the least. | [three boxes with bars] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • Energy of movement is called kinetic energy. • Solid, liquid and gas run from least to most kinetic energy.] |
“Okay, now your turn.” — the attached question
Which state has particles with the most kinetic energy?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
Feedback per option
- A Solid particles only vibrate.
- B Liquid particles slide.
- C Gas particles fly fastest.
Quiz after the video — the mastery check, 11 items
In which state do the particles fly fast in every direction?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
Feedback per option
- A In a solid the particles vibrate on the spot.
- B In a liquid the particles slide past one another.
- C In a gas the particles fly fast in every direction.
What is the scientific name for the energy of movement?
Typed answer
Answer
Accepted: kinetic energy · kinetic
What is kinetic energy?
- A energy of heat
- B energy of movement
- C energy stored in a battery
Answer
Key: B — energy of movement
Feedback per option
- A Heat makes particles move faster, but heat is not kinetic energy. Kinetic energy is the energy of movement.
- B Energy of movement is called kinetic energy.
- C A battery stores energy, but stored energy is not kinetic energy. Kinetic energy is the energy of movement.
Which has particles with more kinetic energy: solid chocolate or melted chocolate?
- A solid chocolate
- B melted chocolate
Answer
Key: B — melted chocolate
So the melted chocolate's particles have more.
Feedback per option
- A Solid particles only vibrate on the spot.
- B Liquid particles slide; solid particles only vibrate.
Which has particles with more kinetic energy: oxygen gas or liquid oxygen?
- A oxygen gas
- B liquid oxygen
Answer
Key: A — oxygen gas
So the oxygen gas's particles have more.
Feedback per option
- A Gas particles fly fastest.
- B Liquid particles slide; gas particles fly.
Which has particles with more kinetic energy: liquid iron in a furnace or a solid iron bar?
- A the solid iron bar
- B the liquid iron
Answer
Key: B — the liquid iron
So the liquid iron's particles have more.
Feedback per option
- A Solid particles only vibrate on the spot.
- B Liquid particles slide; solid particles only vibrate.
Which has particles with more kinetic energy: solid rock or melted rock (lava)?
- A melted rock
- B solid rock
Answer
Key: A — melted rock
So the melted rock's particles have more.
Feedback per option
- A Liquid particles slide; solid particles only vibrate.
- B Solid particles only vibrate on the spot.
Which has particles with more kinetic energy: dry ice (solid carbon dioxide) or carbon dioxide gas?
- A dry ice
- B carbon dioxide gas
Answer
Key: B — carbon dioxide gas
So the carbon dioxide gas's particles have more.
Feedback per option
- A Solid particles only vibrate on the spot.
- B Gas particles fly fastest.
Which has particles with more kinetic energy: liquid nitrogen or nitrogen gas?
- A liquid nitrogen
- B nitrogen gas
Answer
Key: B — nitrogen gas
So the nitrogen gas's particles have more.
Feedback per option
- A Liquid particles slide; gas particles fly.
- B Gas particles fly fastest.
Which state has particles with the most kinetic energy?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
Feedback per option
- A Solid particles have the least.
- B Liquid particles are in the middle.
- C Gas particles fly fastest and have the most.
Which state has particles with the least kinetic energy?
- A solid
- B liquid
- C gas
Answer
Key: A — solid
Feedback per option
- A Solid particles only vibrate, so they have the least.
- B Liquid particles are in the middle.
- C Gas particles have the most.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Why gas particles have the most kinetic energy
MAT-019b · Explain why kinetic energy differs across states — Explain why particles in a gas have more kinetic energy than particles in a solid.
Script
| Say | Screen |
|---|---|
| Here is a pan of cold water at 20 degrees Celsius on a stove. | [pan; label 20 °C] |
| The burner heats it. | [flame; thermometer rises] |
| At 100 degrees Celsius, steam rises off the pan. | [label 100 °C; steam rises] |
| In the cold water the particles slid past one another. | [magnifier on the water: liquid box] |
| In the steam the same particles fly. | [magnifier on the steam: gas box] |
| Where did the extra kinetic energy, the energy of movement, come from? | [question mark] |
| It came from the burner. | [flame highlighted] |
| The faster a particle moves, the more kinetic energy it has. | [short arrow, long arrow; bar grows] |
| Heating gives particles energy and speeds them up. | [flame; arrows lengthen] |
| The burner gave energy to the water particles, minute after minute. | [clock; arrows lengthen step by step] |
| The particles that became steam took in the most energy. | [fast particles leave the surface] |
| So they move fastest, and carry the most kinetic energy. | [gas box bar: MOST] |
| The same holds for any substance: a gas has taken in more energy than the same substance as a liquid, and a liquid more than a solid. | [labels swap to wax; three bars] |
| So, heating gives particles energy and speeds them up. | [the rule slide: the pan on the burner; arrows lengthen; chip HEATING: FASTER; nothing else printed] |
| A gas has taken in the most energy, so its particles move fastest and have the most kinetic energy. | [the gas box bar: MOST] |
| In the pan, the burner heated the water and gave its particles energy. | [pan; flame] |
| The particles that took in the most now fly as steam, with the most kinetic energy. | [steam particles flying] |
| Okay, now your turn. | [the rule slide's images hold; closing screen: bullets — • Heating gives particles energy and speeds them up. • A gas has taken in the most energy. • Its particles move fastest and have the most kinetic energy.] |
“Okay, now your turn.” — the attached question
A pan of water is heated on a stove until steam rises. Where does the steam particles' extra energy come from?
- A the burner
- B the metal of the pan
- C the air in the kitchen
Answer
Key: A — the burner
Feedback per option
- A The burner gives energy to the water particles.
- B The pan only passes the burner's energy on.
- C The kitchen air is cooler than the steam.
Quiz after the video — the mastery check, 10 items
Milk is warmed from 5 °C to 60 °C. What happens to the speed of its particles?
- A They move more slowly.
- B Their speed does not change.
- C They move faster.
Answer
Key: C — They move faster.
Feedback per option
- A Heating speeds particles up.
- B Heating changes the speed of the particles.
- C Heating makes particles move faster.
What is kinetic energy?
- A energy of heat
- B energy of movement
- C energy stored in a battery
Answer
Key: B — energy of movement
Feedback per option
- A Heat makes particles move faster, but heat is not kinetic energy. Kinetic energy is the energy of movement.
- B Energy of movement is called kinetic energy.
- C A battery stores energy, but stored energy is not kinetic energy. Kinetic energy is the energy of movement.
A drop of rubbing alcohol on a desk turns into a gas within a minute. Which have more kinetic energy: the gas particles or the liquid particles?
- A the liquid particles
- B both have the same kinetic energy
- C the gas particles
Answer
Key: C — the gas particles
Faster particles have more kinetic energy.
Feedback per option
- A The liquid particles slide; the gas particles fly faster.
- B The gas particles move faster, so they have more kinetic energy.
- C The gas particles move fastest.
Ice is heated. It melts into water, and the water then boils into steam. Explain why the steam particles have more kinetic energy than the ice particles.
Starter: The steam particles have more kinetic energy because…
Answer
Model answer · ['the steam particles move faster', 'heating gives particles energy and speeds them up', 'the steam has taken in more energy than the ice'] points
Heating gives particles energy and speeds them up.
The steam has taken in more energy than the ice.
So the steam particles move faster and carry more kinetic energy.
Eli says: "Steam has more kinetic energy than liquid water because steam has more particles." Is Eli correct?
- A yes
- B no
Answer
Key: B — no
Heating gave them more energy.
The number of particles is not the reason.
Feedback per option
- A More particles is not the reason. Each steam particle moves faster than a liquid water particle, so each has more kinetic energy.
- B Each steam particle moves faster than a liquid water particle, so each steam particle has more kinetic energy.
A candle burns. Some of its solid wax melts into liquid wax. Which has particles with more kinetic energy?
- A the solid wax
- B the liquid wax
- C both have the same kinetic energy
Answer
Key: B — the liquid wax
The liquid wax has taken in more energy than the solid wax.
So its particles have more kinetic energy.
Feedback per option
- A The solid wax particles only vibrate on the spot.
- B The liquid wax has taken in energy from the flame, so its particles move faster.
- C The liquid wax particles move faster, so they have more kinetic energy.
A puddle dries up in the sun and its water becomes a gas. Which has more kinetic energy per particle: the gas or the puddle water?
- A the puddle water
- B the gas
Answer
Key: B — the gas
The particles that became gas move fastest and have the most kinetic energy.
Feedback per option
- A Liquid particles slide; gas particles fly faster.
- B The gas particles took in energy from the sun and move faster.
Why do gas particles have more kinetic energy than liquid particles of the same substance?
- A They move faster.
- B There are more of them.
- C They are bigger.
Answer
Key: A — They move faster.
The gas has taken in more energy, so its particles move faster.
Feedback per option
- A Heating gives particles energy and speeds them up.
- B The number of particles is not the reason.
- C Particles do not change size.
True or false: heating a substance gives its particles more kinetic energy.
- A true
- B false
Answer
Key: A — true
Faster particles have more kinetic energy.
Feedback per option
- A Heating speeds particles up, and faster particles have more kinetic energy.
- B Heating does change the particles: it makes them move faster, and faster particles have more kinetic energy.
Solid chocolate melts in the sun. Which has particles with more kinetic energy: the melted chocolate or the solid chocolate?
- A the solid chocolate
- B the melted chocolate
Answer
Key: B — the melted chocolate
The melted chocolate's particles have more kinetic energy.
Feedback per option
- A Solid particles only vibrate on the spot.
- B The melted chocolate took in energy from the sun, so its particles move faster.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Summary: Particles and the three states of matter
Script, part 1 (119 words)
| Say | Screen |
|---|---|
| Here is everything we found out about particles and the three states of matter. | [a still: the spoon, the glass of juice and the balloon] |
| Matter is anything that has mass and takes up space. | [chip: MATTER = HAS MASS + TAKES UP SPACE] |
| And all matter is made of particles that are far too small to see. | [the glass of sugar water with its magnifier; chip: PARTICLES] |
| Particles are always moving. They never stop. | [chip: ALWAYS MOVING] |
| Heating makes particles move faster. Cooling makes them move more slowly. | [two liquid boxes: short arrows at 10 °C, long arrows at 80 °C] |
| To tell the three states apart, ask two questions: does it keep its own shape, and does it keep its own volume? | [chips: KEEPS ITS SHAPE? KEEPS ITS VOLUME?] |
| A solid keeps its own shape and its own volume. | [the spoon; two ticks] |
| A liquid keeps its own volume but takes the shape of its container. | [the juice; cross, tick] |
| And a gas keeps neither: it spreads to fill whatever space it is given. | [the syringe; two crosses] |
| Okay, now your turn. | [the spoon, the juice and the syringe hold; closing screen: bullets — • Matter is anything that has mass and takes up space. • All matter is made of particles, always moving. • Heating makes particles move faster; cooling slows them. • Solid: keeps shape and volume. Liquid: keeps volume. Gas: keeps neither.] |
“Okay, now your turn.” — the check question between the parts
Juice is poured from a tall glass into a wide bowl. What does the juice keep?
- A its shape
- B its volume
- C both its shape and its volume
Answer
Key: B — its volume
So the juice keeps its volume.
Feedback per option
- A The juice lies flat in the bowl, so it does not keep its shape.
- B A liquid keeps its volume but takes its container's shape.
- C Only a solid keeps both.
Script, part 2 (146 words)
| Say | Screen |
|---|---|
| Here is everything we found out about the particles inside each state. | [three empty particle boxes] |
| In a solid the particles are packed tightly, touching, in fixed positions. Each particle vibrates on the spot. | [solid box fills; chips: TOUCHING, FIXED POSITIONS, VIBRATES ON THE SPOT] |
| So a solid keeps its shape and its volume. | [the spoon beside the box] |
| In a liquid the particles touch but have no fixed positions. They slide past one another. | [liquid box fills; chips: TOUCHING, NO FIXED POSITIONS, SLIDE PAST] |
| So a liquid takes the shape of its container but keeps its volume. | [the juice beside the box] |
| In a gas the particles are far apart with empty space between them. They fly fast in every direction. | [gas box fills; chips: FAR APART, EMPTY SPACE, FLY FAST] |
| So a gas fills any container it is given. | [the syringe beside the box] |
| Energy of movement is called kinetic energy. | [chip: KINETIC ENERGY] |
| Solid, liquid and gas run from least to most kinetic energy. | [three bars labelled LEAST to MOST] |
| Heating gives particles energy and speeds them up. | [flame; arrows lengthen] |
| So a gas has taken in the most energy, and its particles move fastest and have the most kinetic energy. | [the gas box bar: MOST] |
| Okay, now your turn. | [the three boxes with their bars hold; closing screen: bullets — • Solid: particles touching, in fixed positions, vibrating on the spot. • Liquid: particles touching, no fixed positions, sliding past one another. • Gas: particles far apart, flying fast in every direction. • Kinetic energy rises from solid to liquid to gas.] |
“Okay, now your turn.” — the two questions after part 2
Which state has particles that are far apart and fly in every direction?
- A solid
- B liquid
- C gas
Answer
Key: C — gas
Feedback per option
- A Solid particles touch, in fixed positions.
- B Liquid particles touch and slide.
- C Gas particles are far apart and fly.
A pan of water is heated on a stove. What happens to the speed of the water particles?
- A They move faster.
- B They move more slowly.
- C Their speed does not change.
Answer
Key: A — They move faster.
Feedback per option
- A Heating gives particles energy and speeds them up.
- B Cooling slows particles down; heating speeds them up.
- C Heating changes the particles' speed, not their size.
What to judge
Is this content better than the current alternative students have (PhysicsGraph / Edmentum)?
8/10 on:
- Clear and concise language
- Physics accuracy (read as chemistry accuracy here; his line as pasted for HS Physics)
- No "clangers" (content that causes a problematic misconception)
- Appropriate questions
- Initial testing
- Expansion into harder questions (no exam)
- The tasks should use similar language to that of the lesson
Gut check: better than the alternative? Would a student benefit? Full criteria
Applied without asking
Rulings you have already given; in force on every card above, not re-asked.
- Every video ends “Okay, now your turn.” with one easy, video-dependent question (the XP gate).
- An intro video is at most 120 words and teaches nothing: it opens the question the topic answers.
- A summary video is at most 300 words: everything taught, in order, just before the PP100.
- A lesson script is at most 200 words.
- Each lesson ships as both a video and an article; the article is not under review here.
- The topic lexicon is two sentences per state (arrangement, then movement).
- Lesson videos of 90–100 s are fine; the merged three-way state sort may run to about 130 s.
The topic’s fixed wording (the lexicon the scripts repeat)
- In a solid the particles are packed tightly, touching, in fixed positions. Each particle vibrates on the spot.
- In a liquid the particles touch but have no fixed positions. They slide past one another.
- In a gas the particles are far apart with empty space between them. They fly fast in every direction.
- Heating makes particles move faster. Cooling makes them move more slowly.
Scripts, questions and quizzes are read from the course content as it stands today; the student site for this topic is here.