Topic 2 — Changing state — blueprint for James

What I need from you: 4 decisions

1

Keep evaporation and boiling in one lesson, as the register has them?

MAT-022 is one atom, "predict what happens to a liquid when enough thermal energy is added". Evaporation happens from the surface at any temperature; boiling happens throughout the liquid at one temperature.

one lesson can teach both as two cases of "liquid to gas", with the bubbles-are-water-vapor point made once. Two lessons would each be short.

My recommendation: one lesson, two cases (L03). Keep / split.

2

Teach the state-change names as one map, or one name per lesson?

each lesson coins its own name where it happens (melting in L01, freezing in L02, and so on). L05 then shows the whole map of six names with sublimation added.

the alternative is a naming lesson up front, which would coin six terms before any of them is seen.

My recommendation: one name per lesson, the map at L05. Agree / change.

3

Numeric answers: typed number with the unit, marked exactly?

L08 asks "45 g of ice melts in a sealed bag; what is the mass of the water?" The student types the number.

the page accepts "45", "45 g" and "45 grams"; a wrong unit is marked wrong with a hint to give grams.

My recommendation: yes, typed, unit required in the model answer. Agree / other.

4

Videos: all eight scripted; which could do without?

something moves in six lessons (particles breaking free, locking, flying off, crowding, skipping the liquid, the sealed bag on the balance).

L06 (same substance) and L07 (state the mass law) are explanations a page carries.

My recommendation: mark L06 and L07 "could do without a video". Agree / change.

Topic 2 at a glance — 8 lessons

LessonOpens onFormat
L01Ice meltsA student takes an ice cube out of the freezer.video + article
L02Water freezesA student pours water into an ice-cube tray.video + article
L03Water turns to a gas: evaporation and boilingA puddle sits on a playground after rain.video + article
L04Water vapor turns back to liquidA student takes a can of soda out of the fridge on a warm, humid day.video + article
L05Straight from solid to gasA block of dry ice sits in a bowl at a party.video + article
L06Same substance, different stateA candle burns on a table.article only
L07Mass stays the same when state changesA student seals 50 g of ice in a plastic bag.video + article
L08Work out the mass after a change of stateA sealed bag of ice reads 45 g on a balance.article only
What this topic is, in five lines

Eight lessons, one per atom: MAT-020, 021, 022, 023, 024, 025, 026, 026b.

Each lesson is an article and a video script; the quiz follows either.

Terms coined here: melting (L01), freezing (L02), evaporation and boiling (L03), condensation (L04), sublimation (L05), water vapor (L03).

Every grade 3–5 idea a lesson leans on is retrieved in the scene and asked as one recall question.

Deliberately not taught: melting point and boiling point as named temperatures, the temperature plateau during a change of state, pressure, attractions between particles (all high school or later topics).

Ice melts L01

A student takes an ice cube out of the freezer.

She puts it on a plate in a warm kitchen.

Thirty minutes later the plate holds a small puddle of water.

Nobody touched the ice.

What happened to its particles?

The point, stated first

Why does a solid melt when it warms up?

Heating gives the particles energy.

The particles in the ice vibrate faster and faster.

They break out of their fixed positions.

Now they slide past one another.

The solid has become a liquid.

Video: the particles shaking harder, then breaking loose and sliding — video and article.

Part 1 — MAT-020 — Predict what happens to a solid when thermal energy is added, at the particle level; coin melting

Check: what (a bar of chocolate left in the sun: what happens) → why (free response, fresh case) → misconception item: a student says the ice particles themselves turn into water particles — the key corrects: the same particles, arranged and moving differently → transfer (butter in a warm pan)

Figure: SVG: the solid box turning into the liquid box in three panels, same sixteen particles, heat arrows beneath

Leans on: T1 L04 (heating speeds particles) and T1 L06 (the solid box) — one recall question each; MAT3-040 retrieved by the scene

Part 1q — Fluency quiz: melting — the term from "solid to liquid" and back

Check: fluency

Figure: —

Leans on: —

Water freezes L02

A student pours water into an ice-cube tray.

She puts the tray in a freezer at −18 °C.

Three hours later every cube is solid.

Nobody stirred or pressed the water.

What happened to its particles?

The point, stated first

Why does a liquid freeze when it cools?

Cooling takes energy away from the particles.

The particles in the water move more and more slowly.

They stop sliding past one another.

They lock into fixed positions and only vibrate on the spot.

The liquid has become a solid.

Video: the sliding particles slowing and locking into place — video and article.

Part 1 — MAT-021 — Predict what happens to a liquid when thermal energy is removed, at the particle level; coin freezing

Check: what (melted candle wax cooling on a table) → why (free response) → misconception item: a student says the particles stop moving completely when the water freezes — the key corrects: they still vibrate on the spot → transfer (molten metal poured into a mold)

Figure: SVG: the liquid box turning into the solid box in three panels, cold arrows beneath; the L01 figure run backwards

Leans on: L01 (melting) and T1 L04 (cooling slows particles) — one recall question each; MAT3-041 retrieved

Part 1q — Fluency quiz: freezing

Check: fluency

Figure: —

Leans on: —

Water turns to a gas: evaporation and boiling L03

A puddle sits on a playground after rain.

The sun comes out.

By the afternoon the puddle has gone, and the ground is dry.

Nobody mopped it up.

Where did the water go?

The point, stated first

Where does a liquid go when it turns into a gas?

Heating gives the particles energy.

The fastest particles at the surface fly off into the air as a gas.

Water as a gas is called water vapor.

A liquid turning into a gas from its surface is called evaporation.

Heat a pan of water to 100 °C and particles fly off all through the liquid, as bubbles of water vapor.

That is called boiling.

Video: particles leaving the surface one by one, then bubbles forming inside the boiling water and rising — video and article.

Part 1 — MAT-022 — Predict what happens to a liquid when enough thermal energy is added; coin evaporation, boiling, water vapor

Check: what (wet washing on a line dries: what happened to the water) → why (free response) → misconception item: a student says the bubbles in boiling water are made of air — the key corrects: they are water vapor → transfer (a spill of rubbing alcohol disappears from a desk)

Figure: SVG: two panels — a puddle with particles leaving the surface; a boiling pan with vapor bubbles rising, the bubble drawn as the gas box

Leans on: T1 L04 (heating) and T1 L08 (the gas box) — one recall question each; MAT3-042 and MAT3-044 retrieved by the two scenes

Part 1q — Fluency quiz: evaporation, boiling, water vapor — which name fits each described case

Check: fluency

Figure: —

Leans on: —

Notes

Question 1 above: keep as one lesson or split.

Water vapor turns back to liquid L04

A student takes a can of soda out of the fridge on a warm, humid day.

Within a minute the outside of the can is covered in drops of water.

The can was dry when it came out.

Where did the water come from?

The point, stated first

Where do the drops on a cold can come from?

The air holds water vapor: water particles flying about as a gas.

Heat flows from the warm air to the cold can, so the air next to the can cools.

Water vapor particles that hit the cold can slow down.

They crowd together, touching, and slide past one another.

The gas has become a liquid on the can.

A gas turning into a liquid is called condensation.

Video: vapor particles hitting the cold surface, slowing and crowding into drops — video and article.

Part 1 — MAT-023 — Predict what happens to a gas when thermal energy is removed; coin condensation

Check: what (a bathroom mirror fogs during a hot shower: what forms on it) → why (free response) → misconception item: a student says the water leaked out through the can — the key corrects: it came from the water vapor in the air → transfer (dew on grass on a cool morning)

Figure: SVG: the gas box beside the cold can turning into the liquid box on its surface, cold arrow; licensed photo of a cold can with drops if one is found

Leans on: L03 (water vapor) and T1 L04 (cooling) — one recall question each; ENE-021 (heat flows from hot to cold) stated in one sentence, not assumed; MAT3-045 retrieved

Part 1q — Fluency quiz: condensation

Check: fluency

Figure: —

Leans on: —

Straight from solid to gas L05

A block of dry ice sits in a bowl at a party.

Over the evening the block shrinks and disappears.

The bowl stays dry: no puddle, no water.

Ice would have left a puddle.

Where did the dry ice go?

The point, stated first

Can a solid turn into a gas without melting first?

Dry ice is solid carbon dioxide.

Warm it and its particles fly straight off the solid into the air as a gas.

The particles never slide as a liquid in between.

A solid turning straight into a gas is called sublimation.

Melting goes solid to liquid; sublimation skips the liquid altogether.

Video: particles leaving the solid block directly, no liquid stage, beside a melting ice block for contrast — video and article.

Part 1 — MAT-024 — Distinguish sublimation from melting by identifying which phase change skips the liquid state; coin sublimation

Check: example sequence: melting (ice → puddle) vs sublimation (dry ice → gas, no puddle), then fluency quiz: melting or sublimation on six described cases (a mothball shrinking in a wardrobe, frost disappearing from a cold windscreen on a dry day, butter in a pan…) → misconception item: a student says the dry ice melted very fast — the key corrects: no liquid ever formed

Figure: SVG: the state-change map — solid, liquid, gas as the three boxes with the arrows melting, freezing, evaporation/boiling, condensation, and sublimation drawn straight from solid to gas

Leans on: L01 (melting) and L03 (gas) — one recall question each

Part 1q — Fluency quiz: sublimation

Check: fluency

Figure: —

Leans on: —

Same substance, different state L06

A candle burns on a table.

Wax near the flame melts and runs down the side.

At the bottom it cools and hardens into lumps.

Is the hardened lump still the same wax?

Is the melted wax still wax at all?

The point, stated first

Does a substance become something new when it changes state?

The wax particles never changed.

When the wax melted, the same particles broke out of fixed positions and slid.

When it hardened, the same particles locked back into fixed positions.

Only the arrangement and the movement of the particles changed.

So melted wax is still wax, and hardened wax is still wax.

A change of state never makes a new substance.

Video: nothing a page cannot show — article only (the L01 and L02 figures already carry the picture).

Part 1 — MAT-025 — Explain why melting, freezing or evaporating a substance does not change what the substance is

Check: what (ice melts in a glass: is the liquid still water) → why (free response) → misconception item: a student says steam is a different substance from water — the key corrects: same particles, different arrangement and movement → transfer (frozen orange juice thawed: still orange juice)

Figure: SVG: three boxes in a row — solid, liquid, gas — with the same sixteen particles, captioned "the same particles every time"

Leans on: L01, L02, L03 (the three changes) — one recall question; MAT3-046 retrieved

Mass stays the same when state changes L07

A student seals 50 g of ice in a plastic bag.

The bag reads 50 g on a balance.

She leaves it on the bench until every piece has melted.

She weighs the bag of water.

What does the balance read?

The point, stated first

Does a substance lose or gain mass when it changes state?

The bag still reads 50 g.

Every particle that was in the ice is still in the bag as water.

No particle left, and no particle arrived.

So the mass does not change when a substance changes state.

Video: the balance reading holding at 50 g while the ice melts — video and article (short).

Part 1 — MAT-026 — State that the mass of a substance does not change when it changes state

Check: what (a sealed bottle of water is frozen: what happens to its mass) → why (free response) → misconception item: a student says the water weighs less than the ice because water is "lighter" — the key corrects: the same particles, so the same mass → transfer (butter melted in a sealed tub)

Figure: SVG: the sealed bag on the balance, before and after, both reading 50 g, with the particle boxes beneath

Leans on: L06 (same particles) and T1 L01 (mass on a balance) — one recall question each; MAT5-062 retrieved by the scene

Work out the mass after a change of state L08

A sealed bag of ice reads 45 g on a balance.

The ice melts completely inside the bag.

A student is asked for the mass of the water, in grams.

She has not weighed the bag again.

Can she still give the answer?

The point, stated first

How do you find the mass after a change of state?

The mass does not change when a substance changes state.

So the mass of the water equals the mass of the ice.

The water has a mass of 45 g.

If some of the substance escapes as a gas, the mass left behind is the mass before minus the mass that escaped.

Video: nothing beyond L07 — article only, with the worked example on the page.

Part 1 — MAT-026b — Calculate the mass of a substance after a change of state given its mass before

Check: scaffolded sequence (type b): worked example on the page (45 g of ice → 45 g of water), then typed numeric items — sealed bag freezes (mass before given, surplus temperature to ignore) → sealed tub melts → an open pan boils and a stated mass of steam escapes (mass before minus mass escaped) → one fresh bare item

Figure: table: three worked cases side by side — before, the change, after

Leans on: L07 (the mass law) — one recall question

Topic close

Mixed mastery practice: 10–12 items across the eight atoms in a mixed order; the six coined names by recall (the student types the name from a described change); two typed numeric items; two short written answers (explain melting at the particle level; explain why the mass holds).

Then the PP100: 20 four-option MCQs on fresh instances, tagged easy / medium / hard by depth of reasoning, at least one item per atom.

The course architecture (14 topics) — open only if you want the whole map

Skill: course-build → atomise (architecture, step 6b gate) → write-like-james @ 4c9e849

MS Chemistry — course architecture v1 (for James's approval, 25 September 2026)

Read this in five minutes. It decides the topics, their order, where every PP100 sits, and which topic pilots first. Nothing below writes a lesson sentence. The atom register stays where it is: the Matter strand of the Science Knowledge Graph (92 atoms, JM-reviewed). This document arranges those 92 atoms into a course and stops.

The takeaways

Status (25 September, later the same day): you approved Topic 1 as the pilot and clarified delivery (video or article per atom, then questions). Card 5 records that. The ask now: approve or edit the Topic 1 blueprint (course_preview/review/BLUEPRINT_T01.html); lesson writing starts on your word.


Card 1 — The topics

The call: fourteen topics in the order below, a mixed mastery practice set then a PP100 at the end of every one.

#Topic (student-facing title)AtomsLessonsTEKS stampThe big idea it serves
1Particles and the three states of matterMAT-001, 002, 003, 004, 016, 016b, 017, 017b, 018, 018b, 019, 019b126.6AEverything is made of moving particles; that explains solids, liquids and gases
2Changing stateMAT-020, 021, 022, 023, 024, 025, 026, 026b86.6A (NGSS MS-PS1-4)Heating and cooling change how particles move, not what they are; mass holds
3Physical propertiesMAT-005, 006, 007, 012, 01356.6DProperties you can measure without changing the substance
4DensityMAT-008, 009, 010, 011, 01556.6DA property that identifies a substance whatever the sample size
5Pure substances and mixturesMAT-027, 028, 029, 030, 03256.6BSorting matter by how many kinds it contains
6Solutions and separating mixturesMAT-033, 034, 035, 036, 037, 038, 039, 040, 04197.6D, 7.6E, pre-6.6BA mixture keeps its parts' properties, so you can pull it apart
7Atoms, elements, molecules and compoundsMAT-042, 042b, 043, 044, 045, 046, 047, 04887.6AOne kind of atom or more than one: the particle-level sort
8Inside the atomMAT-049, 050, 051, 051b, 0525(NGSS MS-PS1-1; FL SC.8.P.8.7)Protons decide which element an atom is
9The periodic tableMAT-053, 054, 054b, 055, 056, 057, 05876.6CThe table arranges elements so position predicts properties
10Chemical formulasMAT-059, 059b, 060, 06147.6BA formula counts atoms; change the count and you change the substance
11Physical and chemical changeMAT-062, 063, 064, 064b, 065, 065b67.6CDid a new substance form? The one test, and its evidence
12Chemical reactions and conservation of massMAT-066, 067, 068, 069, 069b, 070, 071, 07288.6E, 8.6BReactions rearrange atoms; none appear or vanish, so mass holds
13Water's special propertiesMAT-073, 074, 075, 07648.6CWater particles pull on each other and on other surfaces
14Acids and basesMAT-077, 078, 079, 080, 081, 08268.6DTwo families of substance, one scale, and what happens when they meet

Totals: 92 lessons, 14 practice sets, 14 PP100s (280 items), 3 checkpoint tests. Two atoms may need a second lesson once blueprinted — MAT-010 (calculate density) and MAT-061 (coefficients and parentheses) — so plan for 92 to 94.

Why this grouping

What changes: the course folder gets one topicNN_build/ folder per topic; Topic 1's blueprint is written; nothing else is authored until you approve it.


Card 2 — Topic 1 is the pilot, at 12 lessons

The call: pilot "Particles and the three states of matter" end to end — 12 lessons, quiz after each, mixed practice, PP100 — before any other topic starts.

Why

The alternative is a 10/10 cut: move the two kinetic-energy atoms (MAT-019, 019b) to the front of Topic 2, where kinetic energy is the lever for melting. I kept them in Topic 1 because TEKS 6.6A names kinetic energy in the states comparison, and the ranking closes the three-box picture.

What changes: the Topic 1 blueprint is the next thing you read.


Card 3 — Density stands alone

The call: Topic 4 "Density" (5 atoms) is separate from Topic 3 "Physical properties" (5 atoms).

Why

What changes: two PP100s where the register had one sub-domain.


Card 4 — Checkpoints at three seams

The call: three static checkpoint tests, each with some free response, at the ends of Topics 6, 10 and 14; the third doubles as the end-of-course test and is anchored to released grade-8 STAAR, Florida SSA and AZSCI items.

Why

What changes: nothing yet. Checkpoints are built after the topics they cover.


Card 5 — Delivery: video or article per atom, quiz straight after

The call: every lesson (one per atom) ships as BOTH a 40–90 second video and a short article, and the student chooses which to take; the quiz follows in the app, never inside the video. At topic end: mixed mastery practice (any format, key terms by recall), then the PP100 (20 MCQs, easy/medium/hard). No topic intro or summary videos.

Why

Skills that run per lesson, in order: write-lesson (dispatching by lesson type) for the article → write-video-script for the video → design-check-sequence then write-mcqs for the quiz → review-accuracy (a reader who did not write it, against the reference) → review-figures on every rendered figure → review-lesson (blind key read, guidance read, adjudication) → blind review of every key before anything ships.

Figures: the blueprint names the figure kind per part. Particle pictures are always monochrome SVG drawings, one depiction reused everywhere. Real scenes a student should recognise (a tea bag colouring water, sand pouring into a jar) are licensed stock photos where the photo carries the point; a drawing where the point is a measurement or a label.

What changes: the blueprint carries a delivery line and an SVG-or-photo call on every figure.


Card 6 — Five prerequisites are taught in other strands

The call: the five cross-strand prerequisites below are not taught in MS Chemistry. Each lesson that leans on one states the fact in one sentence and asks one recall question before using it.

External atomWhat it saysLeaned on by
ENE-020Temperature measures average particle motionMAT-004 (Topic 1)
ENE-021Heat flows from hot to coldMAT-020–023 (Topic 2)
ENE-025Thermal conductors and insulatorsMAT-013 (Topic 3)
FOR-017Spot a magnetic forceMAT-041 (Topic 6)
LIF-073The photosynthesis word equationMAT-072 (Topic 12)

Why

What changes: the blueprint's "leans on" column names the external atom wherever it applies.


Card 7 — Register observations, no edits made

The call: seven observations for your atomisation pass. I changed nothing in the register.

  1. MAT-013 sorts materials as thermal and electrical conductors — two property families in one behaviour (the "and" audit). Candidate split.
  2. MAT-022 "Evaporation and boiling" — evaporation happens at the surface below the boiling point; boiling happens throughout at one temperature. Two predictions, one atom. Candidate split.
  3. MAT-050 states the charge and location of three particles — six facts in one contrast frame. HS Chemistry kept a similar profile atom whole as an argued exception; flagging for the same argument here.
  4. MAT-061 counts atoms with "a coefficient, parentheses, or both" — two routines, likely two lessons.
  5. MAT-019b may not fail independently of MAT-019 in practice. Kept as its own lesson; the data decides (guide: never pre-emptively merge).
  6. MAT-004 → MAT-016/017/018. Identifying a solid from its behaviour does not need "heating speeds particles". The edge is honoured in the order, but it looks like a sequencing edge rather than a knowledge one.
  7. MAT-042 has no in-strand prerequisite and enters via MAT5-084 only; Topic 7 must open with the particle picture from Topic 1 as its retrieval.

What changes: nothing until you rule. Atom edits happen in the knowledge-graph repo with a log entry.


About this build (kickoff record)

What happens next

You approve or edit the topic table. Then you read the Topic 1 blueprint. Only after that does write-lesson run on Topic 1, one lesson at a time, starting with the first of each lesson type as its exemplar.