Topic 38 — Plant parts and their jobs — blueprint (29 September 2026)
What I need from you: 4 decisions
Does LIF3-022 (what the stem does) become two atoms, as the two lessons here?
the atom's behaviour has two jobs — "it holds the plant up, it carries water from the roots to the leaves" — a payoff that needs a semicolon, which the write-lesson rule reads as two lessons. Authored as L02 (holds it up: the sunflower, the trunk, the snapped stem) and L03 (carries water: the celery in red water, the whole plant, the tall tree), each under 150 spoken words. One lesson carrying both would run to the 75 s cap with no room for the snapped stem or the cut celery.
My recommendation: split, LIF3-022 keeping "holds the plant up" and a new atom (provisional LIF3-P02) taking "carries water from the roots to the leaves", L03's prerequisite being LIF3-021. Written up in records/ATOM_PROPOSALS_G3T38.md; the register is untouched.
Three surprising members are left out on purpose: a potato, a cactus's spines, an onion's layers. Agreed?
the pattern says teach the surprising members of a category first — so a carrot is a root (L01), a tree trunk is a stem (L02), pine needles are leaves (L04, Topic 32's own line). A potato is a stem that neither holds a plant up nor carries water to leaves; cactus spines and onion layers are leaves that do not make the plant's food. Each would show a member that fails the very job its atom states, in a lesson whose whole point is that job.
My recommendation: leave them out of Grade 3; the register's cross field for the three atoms can carry them as a barred list for the bank.
Is "the flower" the fourth option on the bank's which-part items?
a PP100 MCQ needs four options and the topic teaches three parts. Topic 37 (the lesson before this one) taught the flower's job, so "the flower" is a part the student has met, and it is never the key here. The alternative is a fourth plant part nobody has taught.
My recommendation: yes, the flower, always in fourth place after roots, stem, leaves (the fixed set, bottom to top). The reviewer's caveat: an option that is never the key in fifty items becomes one students learn to skip. Two ways to keep it live: (a) accept that — four options is the rule and the flower is the honest fourth; (b) let two or three bank items key on the flower through a Topic 37 retrieval in the same frame ("Which part is where the seeds are made?"). I lean (b); the reviewer does too.
Is the "what happens when a part is cut, bitten, covered or pulled out" form the tenth type?
the quizzes already carry it (roots in the air; the flattened corn; the bitten stem; the leaf in the dark; the snapped poppy) — a genuine two-step that tests each part's job by its consequence, and it descends from the lessons' own quizzes as your Topic 3 rule asks. Nine types are on the sheet; ten is your ceiling.
My recommendation: add it as type 10, medium, four options, one exemplar written after you rule.
Topic 38 at a glance — 4 lessons
| Lesson | Opens on | Format | |
|---|---|---|---|
| L01 | The roots hold the plant in the ground | Here is Leonie in the yard, pulling up a dandelion. | video + article |
| L02 | The stem holds the plant up | Here is Anton beside his sunflower. | video + article |
| L03 | The stem carries water from the roots to the leaves | Here is Marisa with a stick of celery. | video + article |
| L04 | The leaves make the plant's food | Here is Jonas's bean plant on a sunny windowsill. | video + article |
What this topic is, in five lines
Four short lessons on the three parts of a plant that Grade 3 names — roots, stem, leaves — and the job each part does. L01: a plant's roots hold it in the ground, and they take in water from the soil (the second job is Topic 32's, retrieved). L02: a plant's stem holds it up (a tree trunk is a stem). L03: a plant's stem carries water from the roots to the leaves (the celery in red water). L04: a plant's leaves are where it makes its food, using sunlight and water (Topic 32's sentence, exactly; the leaf under foil turns pale). Each lesson is a fact true of every case, taught by an example run with the surprising member first and the everyday member last; L02 carries the one minimal-difference non-example that exists, the same sunflower with its stem snapped.
The register plant is Topic 32's plant drawn before it flowers (the flower's job is Topic 37's); each lesson switches one layer on — a halo and a label on the part, blue water arrows, the Sun's arrows — and a drawn job table fills one row per lesson as its closing return, so L04 ends on the full table. Items use fresh plants throughout (a thorn bush, radishes, a fallen tree, tulips in a vase, a palm, flattened corn, a daisy in blue water, a lawn, a cabbage, a parsnip).
Not taught: how a plant makes its food beyond "using sunlight and water" (no air, no carbon dioxide — Grade 5's); the flower (Topic 37); roots growing down and stems growing toward light (Topic 39).
Applied without asking (rulings you have already given), and after the non-author review (records/REVIEW_G3T38_2026-09-29.md, all 34 rows adjudicated in the build record): hard PP100 items are typed (two of nine exemplars, both text entry); every attached question stands alone with its own drawing; no option bundles a verdict with a reason; every stem a positive question; colour in figures; scene changes spoken with "let's" in the intro and never as an imperative; the intro ends on a ready line and a poll and names no lesson; three questions on the summary; quiz scenes differ from the lesson's; a headache character never appears in an item; a claim-maker is used once per topic; one lesson per one-clause payoff.
The roots hold the plant in the ground L01
Here is Leonie in the yard, pulling up a dandelion.
She tugs.
It won't come.
She tugs harder, and out it comes.
A long white root hangs from it, with soil still clinging on.
What was holding the dandelion in the ground?
The root was under the ground, gripping the soil.
A plant's roots hold it in the ground.
A carrot is a root.
A tree's roots spread out wide under the ground and hold it through a storm.
The roots take in water from the soil.
They do not eat the soil.
Video: the dandelion's root and the clinging soil; the carrot pulled up; the tree in the wind with its roots haloed — video and article.
Part 1 — LIF3-021 — State the jobs of a plant's roots: hold it in the ground; take in water from the soil
Part 1q — quiz, 11 items
The stem holds the plant up L02
Here is Anton beside his sunflower.
The sunflower stands taller than he does.
It has no bones.
So what holds it up?
The sunflower stands on one thin green stem.
A plant's stem holds it up.
A tree trunk is a stem, a very big one.
When the stem snaps, the top flops to the ground.
Video: the stem haloed on the register plant; the trunk; the same sunflower with its stem snapped (a cartoon, the pair to the headache's) — video and article.
Part 1 — LIF3-022 (first job) — State that a plant's stem holds it up; name a tree trunk as a stem
Part 1q — quiz, 10 items
The stem carries water from the roots to the leaves L03
Here is Marisa with a stick of celery.
She stands it in a glass of red water.
The next morning, the leaves at the top have red lines in them.
How did red water get up to the leaves?
Inside the cut stem there is a ring of little red dots.
The red water climbed up inside the stem.
The roots take in water from the soil.
A plant's stem carries water from the roots to the leaves.
A tree's trunk carries water all the way up to the highest leaf.
Video: the red lines, the cut end; the blue arrows climbing the register plant's stem; the arrows up the trunk — video and article.
Part 1 — LIF3-022 (second job; proposed LIF3-P02) — State that a plant's stem carries water from the roots to the leaves
Part 1q — quiz, 10 items
The leaves make the plant's food L04
Here is Jonas's bean plant on a sunny windowsill.
Jonas wraps one leaf in foil, so no light can reach it.
Two weeks later, he takes the foil off.
That leaf is pale yellow.
The other leaves are dark green.
Why did the covered leaf turn pale?
A plant makes its own food in its leaves, using sunlight and water.
Under the foil, no light landed on that leaf: it could not make food, and it lost its green.
Pine needles are leaves.
A lettuce is a bunch of leaves.
Video: the pale leaf among the green; the Sun's arrows and the water arrows meeting at the leaves; the needles and the lettuce — video and article.
Part 1 — LIF3-023 — State that a plant's leaves are where it makes its food, using sunlight
Part 1q — quiz, 12 items
Language decisions
- The atoms' words: "roots", "stem", "leaves" (everyday words Topic 32 used; not coined), "trunk" (named in L02 as a tree's stem).
- Topic 32's sentences stand exactly: "Plants make their own food in their leaves, using sunlight and water."; "The roots take in water. They do not eat the soil." Never "eats soil"; never "drinks".
- "Carries" is the atom's word for the stem's second job. "Holds it up" and "holds it in the ground" are kept apart on every line: the stem holds the plant UP, the roots hold it IN THE GROUND.
- No air, carbon dioxide, photosynthesis or chlorophyll (Grade 5's; LIF3-023's cross field marks the chain). The pale leaf "could not make food" and stops there.
- No growth responses (Topic 39): nothing bends, turns or grows toward anything here.
- Openers vary: L01 "Here's Leonie…", L02 "Here's Anton…", L03 "Here's Marisa…", L04 "Here's Jonas's bean plant…"; contractions in scripts and headaches; "Now consider" / "Now imagine" opens each new scene.
PP100 type sheet (TYPE_SHEET_ONLY; James's 28 Sep night ruling: hard items are typed)
Nine types, nine exemplars, at most two alone-types per atom; seven four-option MCQs (easy and medium) and two typed hard items (the part's name from its two jobs, no other part named in the stem; the missing thing from a pale leaf). Coverage table and the ⟂ draw constraints in records/TYPES_G3T38.md. A tenth type is decision 4.
Figures
52 figures: 21 SVG (the register plant in eight layer states, the tree in three, the snapped stem, the job table in four stages, four rule cards), 26 photos, 5 cartoons (the fifth is the snapped sunflower, L02's non-example). Every figure has an IMAGE_BRIEFS entry and an IMAGE_KINDS entry; people and hands are never drawn as glyphs. Item figures carry no halo, no arrow and no chip. The job table's cells are measured against their columns by a guard asserted at import (worst ratio 0.77).
Deliberately not taught
How the leaves make food beyond "using sunlight and water" (the air the leaves take in, carbon dioxide, the word photosynthesis — LIF4-010 and LIF5-010); why a leaf in the dark turns pale (no mechanism: "it could not make food"); the flower's job (Topic 37); roots growing down and stems growing toward light (Topic 39); a potato as a stem, cactus spines and onion layers as leaves (decision 2); that a green stem also makes a little food (clarity beats accuracy: the leaves are where the food is made); the seed (Topic 37); how water climbs (no tubes named, no mechanism).
This grade’s course architecture — open only if you want the whole map
Skill: course-build → atomise (architecture, step 6b gate) → write-like-james @ acc4fb6
Grade 3 Science — course architecture v3 (James's rulings of 25 September, plus Olivia Mullins's sequencing)
Read this in five minutes. Grade 3 Science is ONE course with a fixed order; nobody picks strands. It arranges the 183 Grade 3 atoms into four strands and forty-two small topics, each with its own mixed practice, summary video and PP100. Nothing below writes a lesson sentence. The atoms stay where they are: the Science Knowledge Graph's 3-5 registers.
Rulings recorded (James, 25 September 2026)
- Strand order: Physics, Matter, Earth & Space, Life. James: "I don't think it matters hugely … Happy to go with 1 Physics 2 Matter 3 Earth and space 4 Life. That works well." Strands may be intermingled later if a reason appears; none does yet.
- Grade 3 is one course. "We're not going to allow students to pick any strand … we need to structure Grade 3 as we think Grade 3 should be structured best." v1's line about students choosing strands was wrong and is gone.
- Topic 1 is the pilot. "That topic 1, I think, works as a good pilot."
- Small topics. "3 atoms is fine for testing. PP100s on quite granular stuff is absolutely fine … A 4-atom topic and a 5-atom topic is great. 9 is too many, really … if something's got 9 atoms, we should be considering splitting it." So sound, soil, fossils and natural resources each stand alone, and every v1 topic of nine or more was split (Card 2). Topics 1 and 2 keep 8 and 7 lessons because James approved Topic 1 as it stands and Topic 2 is one chain about speed; both are flagged as split candidates once their PP100 data arrives.
- Forces opens with Earth's pull and magnets, before the word "force" (Olivia Mullins call, 25 September; James: "I think I'll follow that"). Topics 3 and 4 teach the two non-touching pulls with no talk of forces; Topic 5 coins "force" on both of them and on the hand push together, so the hand push never becomes the whole category. Her two classroom misconceptions (Earth pulls only on your feet; "balanced" is a kind of force) are in the register and the lessons.
- States of matter start with air (Olivia): air takes up space → gases spread → liquids → solids → the sort.
Applied from the earlier rulings: four strands; Motion before Forces before Energy; Scientific Reasoning atoms taught inside the topics that use them; one intro video per strand and per topic, each teaching nothing; one atom, one lesson, both video and article; a summary video before every PP100; PP100 banks of at least fifty items tagged by depth of reasoning; the Forces topics reuse the golden pack; the language rules (Earth's pull, carriers not forms, no "leak" or "lift").
Card 1 — The strands and their order
The call: Physics → Matter → Earth & Space → Life, each with its own intro video and its own end-of-strand test.
| Strand | Topics | Atoms | Why it sits here |
|---|---|---|---|
| Physics | 1-15 | 64 | Motion first: what you can see, before the invisible cause. Energy last: "faster means more energy" needs speed. |
| Matter | 16-21 | 22 (+7 Scientific Reasoning) | Uses the measuring tools and feeds Earth's water cycle in Grade 4. |
| Earth & Space | 22-31 | 41 (+4 Scientific Reasoning) | Weather uses tables and graphs; "the Sun powers Earth" must precede food chains. |
| Life | 32-42 | 43 | Ends the year; leans on Space (the Sun), Forces (Earth's pull) and Matter (properties). |
Scientific Reasoning's 13 atoms are spread through Topics 1, 16, 17, 22, 23 and 25 (Card 4). Total 183 lessons.
Card 2 — The topics
The call: forty-two topics, most of three to six lessons; a mixed mastery practice set, a summary video and a PP100 at the end of every one.
| # | Topic (student-facing title) | Atoms (in teaching order) | Lessons | The big idea it serves |
|---|---|---|---|---|
| Physics | ||||
| 1 | Where is it? Did it move? | MOT3-001, 002, 003, 004, 005, 006, 007, 008 (+ SR3-020, 021 inside L07/L08) | 8 | You say where something is with a landmark; moving means its position changed; motions can repeat |
| 2 | Fast and slow | MOT3-020, 021, 022, 023, 024, 025, 026 | 7 | Faster means farther in the same time, or the same distance in less time |
| 3 | Earth pulls things down | FOR3-021, 029, 030, 028, 022 (+ a closing lesson naming gravity) | 6 | Earth pulls every object, all the time, straight down, on every part of it, without touching; a strong enough pull can beat it; the pull's name is gravity (JM 28 Sep 2026; no word "force" yet) |
| 4 | Magnets | FOR3-023, 024, 025 | 3 | A magnet pulls steel without touching; two magnets pull or push; use a magnet to solve a problem (no word "force" yet) |
| 5 | What a force is | FOR3-012, 001, 008, 006 | 4 | Earth's pull, a magnet's pull and your push are all forces; push or pull; on one object; in one direction |
| 6 | Forces that touch, and forces that don't | FOR3-020, 027, 026 | 3 | Some forces act without touching: Earth, magnets, a rubbed balloon; most pushes touch |
| 7 | Pushes and pulls change things | FOR3-002, 003, 004, 005, 007 | 5 | A push or pull starts, stops, turns or squashes; you can test it |
| 8 | Strong or weak: drawing a force | FOR3-009, 010, 011 | 3 | A stronger push makes a bigger change; an arrow shows a force's direction and strength |
| 9 | Balanced forces | FOR3-040, 041, 042, 043, 045 | 5 | Several forces act at once; balanced forces leave motion as it is, still or steady |
| 10 | Unbalanced forces | FOR3-044, 046, 047 | 3 | Unbalanced forces speed up, slow down or turn |
| 11 | Energy: what has it, how it travels | ENE3-001, 002, 003, 004, 005, 034 | 6 | Energy makes things happen; light, sound and electricity carry it; faster means more |
| 12 | Sound | ENE3-030, 031, 032 | 3 | Sound comes from vibration and travels to your ear |
| 13 | Light: sources, straight lines, shadows | ENE3-010, 011, 012, 017 | 4 | Light comes from a source, travels straight, makes shadows, must reach the eye |
| 14 | Light bounces, bends or soaks in | ENE3-013, 014, 015, 016 | 4 | Reflection, refraction, absorption, sorted |
| 15 | Light and heat | ENE3-020, 021, 033 | 3 | Light-givers give heat; rubbing makes heat; light carries energy |
| Matter | ||||
| 16 | Describe it, sort it | SR3-001, 002, MAT3-001, 002, 003 | 5 | Observe with more than your eyes; describe an object by its properties; sort and order |
| 17 | Measuring tools | SR3-003, 004, 005, 006, 007 | 5 | Thermometer, scale, measuring jug; pick the right one; two groups can disagree |
| 18 | Which has more? | MAT3-004, 062, 005, 006 | 4 | More mass, more space, warmer, decided by a measurement; MAT3-062 "everything takes up space" (JM ruling on Olivia's comment, 28 Sep 2026) sits before the space comparison |
| 19 | Sinks, floats, sticks to a magnet: choosing materials | MAT3-007, 008, 060, 061 | 4 | Test a property, then pick the material for the job |
| 20 | Solids, liquids and gases | MAT3-063, 064, 065, 022, 023, 021, 020, 024 | 8 | Air first (Olivia's order): air is something you can feel; it is made of tiny pieces too small to see; so is every kind of matter; air takes up space; gases spread out to fill their space; liquids take their container's shape; solids keep theirs; then the sort with the awkward cases. MAT3-063, 064, 065 were added on 28 Sep 2026 (JM's rulings on Olivia's comments) before MAT3-022 in the chain; eight lessons is over JM's 3–6 size, so the Topic 20 build record (decision 1) proposes a split after MAT3-022 into "Air is something" (4) and "Solids, liquids and gases" (4), renumbering Matter to 16–22, Earth & Space 23–32, Life 33–43 — nothing after Topic 19 is authored, so the renumbering costs nothing now |
| 21 | Heating and cooling | MAT3-040, 041, 042, 043, 044, 045, 046 | 7 | Heating and cooling change the state but it is the same water (split candidate: melting/freezing vs evaporating/condensing) |
| Earth & Space | ||||
| 22 | Measuring the weather | EAR3-017, 018, 019, SR3-010, EAR3-020, SR3-011 | 6 | Three instruments, a weather diary, reading it back |
| 23 | Weather over a season, and far away | SR3-012, EAR3-022, 023, 021, 024 | 5 | A season's records make a chart; the chart predicts; other places differ |
| 24 | Volcanoes, earthquakes, landslides | EAR3-007, 010, 008, 011, 009, 012 | 6 | What each one is, then how it changes the land fast |
| 25 | Dangerous weather | EAR3-013, 014, SR3-022 | 3 | Weather can do damage; a defence holds it back; pick the sensible cause |
| 26 | Soil | EAR3-001, 002, 003, 004 | 4 | Soil is broken rock plus dead things |
| 27 | Fossils | EAR3-029, 030, 031, 032, 033 | 5 | A few dead things last as fossils and tell of the past |
| 28 | Using and conserving natural resources | EAR3-040, 041, 042, 043 | 4 | Everything you own started as a natural resource; some run short |
| 29 | The Sun | SPA3-001, 007, 002 | 3 | A huge glowing ball of gas; a star; the source of Earth's energy |
| 30 | The stars | SPA3-003, 004, 005, 006 | 4 | Stars differ; they look like dots because they are far; telescopes show more |
| 31 | The solar system | SPA3-010, 011, 012, 013, 014 | 5 | Earth orbits the Sun with seven other planets; the Moon orbits Earth |
| Life | ||||
| 32 | Alive or not | LIF3-001, 007, 008, 009, 002 | 5 | Living things grow, feed, move and make more; sort living from non-living |
| 33 | What living things need | LIF3-003, 004, 005, 006 | 4 | Food, water, air and a place that suits them |
| 34 | Backbone or no backbone | LIF3-010, 011, 070 | 3 | Grouping by shared features; vertebrates, invertebrates, arthropods |
| 35 | The five vertebrate groups | LIF3-015, 016, 017, 018, 019, 012 | 6 | Mammal, bird, reptile, amphibian, fish, then the sort |
| 36 | Eggs, body parts and senses | LIF3-013, 020, 027 | 3 | Egg-layers or live birth; body parts do survival jobs; animals sense, then respond |
| 37 | How plants make new plants | LIF3-071, 072, 014, 024 | 4 | Seeds, spores, the sort, the flower's job |
| 38 | Plant parts and their jobs | LIF3-021, 022, 023 | 3 | Roots, stem, leaves |
| 39 | Plants respond | LIF3-025, 026, 028 | 3 | Stems grow to the light, roots grow down; plants respond by growing, animals by moving |
| 40 | Life cycles and family likeness | LIF3-030, 031, 040, 041, 042 | 5 | Every life runs in a cycle; offspring take after their parents but differ |
| 41 | Food chains | LIF3-050, 051, 052 | 3 | Every food chain starts with the Sun; remove a link and the rest changes |
| 42 | Living together and coping with change | LIF3-060, 061, 062, 063 | 4 | Groups, places and seasons decide who survives |
Totals: 183 lessons, 42 practice sets, 42 PP100s (banks of at least 50 items each), 4 strand tests (after Topics 15, 21, 31, 42), 1 end-of-grade test.
Why this grouping
- Every prerequisite edge points backwards in this order. Checked atom by atom in the assembled files; no forward reference.
- Animal topics (33-35) and plant topics (36-38) are separate, as James asked; the plant-versus-animal response contrast (LIF3-028) closes Topic 38 because it needs both sides taught.
- Topics 3 and 4 teach Earth's pull and magnets without the word force; Topic 5 coins it on all three kinds (Olivia's sequence). Topic 8 carries the two force-arrow atoms so Topics 9 and 10 can draw balanced and unbalanced forces.
- Topic 24 puts "what a volcano is" straight before "volcanoes change the land fast", and the same for earthquakes and landslides: what it is, then what it does.
What changes: the folder gets grade3/topicNN_build/ per topic; Topic 1's blueprint is approved; Topic 1 is built first.
Card 3 — Topic 1 is the pilot (approved)
The call: pilot "Where is it? Did it move?" end to end — 8 lessons, an attached question per video, a ten-item quiz after each, mixed practice, summary video, PP100 — before any other topic starts.
- It is the first thing a Grade 3 student meets, so the whole format ladder gets tried where the stakes are lowest.
- It holds a fact, four sorts, two routines and a prediction. Every check type the course needs appears once.
- Its quiz items are drawings of everyday scenes, so the figure pipeline for young grades gets tested too.
- Topics 3 to 10 follow, reusing the golden Forces pack where its lessons match (push or pull, force on one object, strength, direction, more than one force, the balanced and unbalanced lessons).
Card 4 — Scientific Reasoning is taught where it is used
The call: each of the 13 Scientific Reasoning atoms is a lesson inside the topic that first needs it, with its check there; no separate strand, no separate test.
| SR atom | Host topic | Why there |
|---|---|---|
| SR3-001 Observe with more than your eyes; SR3-002 Observation or idea about it? | 16 Describe it, sort it | describing an object's properties is observing |
| SR3-003 Read a thermometer; SR3-004 Measure mass with a scale; SR3-005 Measure the volume of a liquid; SR3-006 Pick the right measuring tool; SR3-007 Two groups, two different answers | 17 Measuring tools | the tools before "which has more?" uses them |
| SR3-010 Record results in a table; SR3-011 Find a value in a table | 22 Measuring the weather | the weather diary is the first table students fill and read back |
| SR3-012 Read a pictograph or bar graph | 23 Weather over a season | the graph before the graphing routine |
| SR3-020 Spot the pattern; SR3-021 Use the pattern to predict | 1 Where is it? Did it move? (inside L07 and L08) | the swing's repeat is the pattern |
| SR3-022 Choose the sensible cause | 25 Dangerous weather | first place students pick a cause for an event |
Card 5 — Tests and benchmarks
The call: a PP100 per topic; a static end-of-strand test per strand (some free response); one static end-of-grade test; all Grade 3 tests are our own banks, seeded from released grade-5 items filtered to Grade 3 atoms.
- No state tests science before grade 5 (D1 ruling). The released STAAR, Florida SSA and AZSCI grade-5 forms give the style and difficulty; items tagged to Grade 3 atoms seed the banks.
- The strand tests fall after Topics 15, 21, 31 and 42.
- The end-of-grade test samples all four strands with free-response items.
What happens next
Topic 1 is built as the first interactive version for James: the topic intro (video script and article), eight lessons each as a video script with animation guidance and an article with figures, one attached question per video, a ten-item quiz per lesson, mixed practice, the summary video script and the PP100 bank. Topic 3 follows, reusing the golden pack.