Skill: course-build → write-mcqs → write-explanation, design-check-sequence @ 4a6e93d · write-mcqs (typed hard type) @ 11cce8f
Topic 4 — Magnets — the PP100's seven question types, one exemplar each
What this page is. James approves a bank's question TYPES before the bank is generated (vault: A bank is reviewed as its question types first, one exemplar each, 28 Sep 2026; James, 28 Sep: "by default, it's unlikely that you're going to need more than two question types per atom, and often you'll just need maybe five question types"). Seven types for three atoms (six, plus the pair type the non-author review asked for); this sheet writes ONE exemplar per type in full, exactly as it sits in content/G3T04.py (PP100, flagged TYPE_SHEET_ONLY). No other bank item exists yet. Once the types stand, about fifty items are generated from them, varying scene, nouns and stuff, easy-heavy, type 6 carrying at most eight.
Revised 28 Sep 2026 (night) after James's typed-entry ruling. James: "PP100s can have text entry or numeric entry… we should prioritize text entry as a sort of harder question type… hard questions would be text entry or even numeric entry if it is a numerical question." So the sheet's one hard type, type 6, is now text entry: the student types the counterexample to a named student's claim instead of picking it from four happenings. Types 1–5 and 7 (easy and medium) stay four-option MCQs and remain the bulk of the bank. No numeric type: this topic has no scale, table or count to read. The old MCQ form of type 6 is kept below the exemplar as history. This also closes the note on the negative stem ("shows that Nora is wrong"): the typed stem is positive.
Why type 6 is the hard end, typed. Recognising the aluminum can among four happenings was a judgement over given cases; producing "aluminum" with nothing to pick from asks for the same judgement (Nora's claim falls only to a METAL a magnet does not pull, so "wood" is no answer) plus the recall of which metal the lesson showed staying, and then the word itself. Production, not recognition, is what makes the item hard (vault: PP100 mastery tests and lesson checks are different jobs, typed-entry refinement, 28 Sep 2026). Hard because, in one line: reject "metal = steel", recall the metal that stayed, type its name.
Revised 28 Sep 2026 (evening) after the non-author review (REVIEW_G3T04_2026-09-28.md): the coverage table added (M2) with type 7 (FOR3-024 + 025) and type 3 widened to the steel-nail instance (023 + 024); PP-5 re-instanced as Lena's aluminum water bottle (M3); PP-4 is Yusuf's shed door and PP-6's claimant is Nora (S14); the rows below run in type order. Every type reuses a form the lesson quizzes and the mixed practice already use, with four options (James's Topic 3 night ruling).
How to read a type line. Each says what the stem asks, what the four options are (the kind of thing), and gives its exemplar scene. Every easy and medium item is a four-option MCQ with a why (no per-option feedback in the bank; the engine prints Correct / Not quite); the hard item is text entry with an accept list (the grader lower-cases, trims and drops a final period, and matches exactly — it does not drop articles, so "the aluminum can" and "aluminum can" are both listed) and a why in the lesson's words. Tags follow depth of reasoning: easy = one one-step sort or recall; medium = a fresh case or a design step; hard = a judgement of a claim against four true happenings. No option bundles a verdict with a reason; every stem is a positive question; no figure carries an arrow or shows the motion the item asks about. The word "force" is not used; "attract" is not used; the aluminum can is the topic's metal-but-not-steel case.
Coverage — every atom alone and in a pair
| Atom | Alone | In a pair |
|---|---|---|
| FOR3-023 a magnet pulls steel, not every metal, without touching | types 1, 2, 6 (Nora's claim) | 5 (with 025); 3, nail instance (with 024) |
| FOR3-024 two magnets pull together or push apart; turn one and pull changes to push; a magnet never pushes steel | types 3, 6 (Mia's claim) | 3, nail instance (with 023); 7 (with 025) |
| FOR3-025 solve a problem with a magnet | type 4 | 5 (with 023); 7 (with 024) |
No row is empty; every pair has a type.
The seven types
| Type | Item | Atom | Tag | The stem asks… | The four options are… | Exemplar scene |
|---|---|---|---|---|---|---|
| 1 | PP-1 | FOR3-023 | easy | which of four named things, each with its stuff, jumps to a held magnet | four things: one steel, and one each of plastic, wood, aluminum (the metal that is not steel) | a straw, a block, a can, a nail |
| 2 | PP-2 | FOR3-023 | easy | what pulled a steel thing up to a magnet held above it, when nothing touched it | the magnet, Earth (pulls down), the air, the surface it lay on | a steel bottle cap on a table |
| 3 | PP-3 | FOR3-024 (+ 023 in the nail instance) | medium | what one magnet did to the thing it came close to — another magnet (slid away, or slid closer) OR a steel nail (slid closer, whichever way the magnet faced) — given what that thing did before they touched | four happenings: pushed it away / pulled it closer / picked it up / did nothing to it; the nail instance is keyed "pulled it closer" | Ana's magnets on a desk |
| 4 | PP-4 | FOR3-025 | medium | what must be added to a wooden (or plastic) thing so a magnet has something to pull | a steel plate, and a plate or card of plastic, wood, paper | Yusuf's shed door |
| 5 | PP-5 | FOR3-025 + 023 | medium | what happens when a magnet is put on a named stuff to hold something | four happenings: it holds / the magnet falls off / the thing tips or swings / the note sticks by itself | Lena's aluminum water bottle |
| 7 | PP-6 | FOR3-024 + 025 | medium | what to fix to two things so a magnet's pull joins them and hands can part them again | four fixings, one on each thing: a magnet / a steel plate / a wooden peg / a plastic clip | two toy boats on the water |
| 6 | PP-7 | FOR3-023 or 024 | hard — TEXT ENTRY | a named student makes a claim; the student TYPES the counterexample — two claims only: "a magnet pulls everything made of metal" (023: type the name of one metal that stays where it is when a magnet comes close → aluminum) and "two magnets always stick together" (024: type what else two magnets can do when they come close → push apart) | no options: a typed word or phrase in the lesson's own words, checked against an accept list (below) | Nora's claim |
Order in the file: easy → medium → hard (PP-1 … PP-7; types 1, 2, 3, 4, 5, 7, 6). Keys of the six MCQs: D C C A D B — no letter over 35 %; PP-7 is typed and has no key letter.
Typed share of the bank. About fifty items; type 6 carries at most eight (the hard tail), split between the two claims with fresh claimants, so about one item in six is typed and the rest are MCQs, easy-heavy — as James asked ("prioritize easy questions").
The exemplars, in full
Type 1 — PP-1 · FOR3-023 · easy
Stem: A magnet is held near four things, one at a time. Which one jumps to the magnet?
- a) a plastic straw
- b) a wooden block
- c) an aluminum can
- d) a steel nail ← key
Why: A magnet pulls steel. / The nail is steel, so it jumps to the magnet. / A magnet does not pull plastic, wood or aluminum, so the straw, the block and the can stay where they are.
Type 2 — PP-2 · FOR3-023 · easy
Stem: A magnet is held just above a steel bottle cap on a table, and the cap jumps up. What pulled the cap up?
- a) the table
- b) Earth
- c) the magnet ← key
- d) the air
Why: The cap is steel. / A magnet pulls steel without touching it. / So the magnet pulled the cap up. / Earth pulls the cap down, not up; the table and the air did not pull it.
Type 3 — PP-3 · FOR3-024 · medium
Stem: Ana slides one magnet toward another on a desk, and the other magnet slides away before they touch. What did Ana's magnet do to the other magnet?
- a) It pulled the other magnet closer.
- b) It picked the other magnet up.
- c) It pushed the other magnet away. ← key
- d) It did nothing to the other magnet.
Why: The other magnet slid away before the magnets touched. / Nothing touched it. / Two magnets can push apart without touching. / So Ana's magnet pushed the other magnet away.
Type 4 — PP-4 · FOR3-025 · medium
Stem: Yusuf wants a magnet to keep his wooden shed door shut. What must he add to the door for the magnet to pull?
- a) a steel plate ← key
- b) a plastic plate
- c) a wooden plate
- d) a paper card
Why: The door is wood, and a magnet does not pull wood. / A magnet pulls steel. / So Yusuf adds a steel plate, and the magnet has steel to pull. / Plastic, wood and paper give the magnet nothing to pull.
Type 5 — PP-5 · FOR3-025 + FOR3-023 · medium
Stem: Lena puts a magnet on her aluminum water bottle to hold a note. What happens?
- a) The magnet holds the note on the bottle.
- b) The bottle tips over.
- c) The note sticks to the bottle by itself.
- d) The magnet falls off the bottle. ← key
Why: The bottle is aluminum. / Aluminum is a metal, but it is not steel. / A magnet does not pull aluminum. / So nothing holds the magnet on the bottle, and Earth pulls it down: the magnet falls off.
Type 7 — PP-6 · FOR3-024 + FOR3-025 · medium
Stem: Two toy boats are to join on the water and come apart again easily. What goes on the end of each boat?
- a) a steel plate on each boat
- b) a magnet on each boat ← key
- c) a wooden peg on each boat
- d) a plastic clip on each boat
Why: The boats must pull together and come apart again. / Two magnets pull together without touching, and hands can pull them apart. / A steel plate does not pull another steel plate; wood and plastic pull nothing. / So a magnet goes on each boat.
Move line: the student chooses what to fix to two things so a magnet's pull joins them (another magnet), four fixings as options. Fresh against L03's train cars: a different vehicle, on water, not drawn.
Type 6 — PP-7 · FOR3-023 · hard · TEXT ENTRY
Hard because: the student must see that Nora's claim falls only to a METAL a magnet does not pull (steel is not the whole of metal, and wood is no answer), recall which metal the lesson showed staying, and produce its name with no options to recognise it from.
Stem: Nora says a magnet pulls everything made of metal. Type the name of one metal that stays where it is when a magnet comes close.
Accept (exact match after lower-casing, trimming and dropping a final period; the first entry is what the engine shows after a miss): aluminum · aluminium · aluminum can · an aluminum can · the aluminum can · soda can · a soda can · the soda can · aluminum soda can · an aluminum soda can · the aluminum soda can · aluminum foil · the aluminum foil · a sheet of aluminum foil · copper · gold · silver · brass · tin
The can and foil forms are there because the lesson's non-example is the aluminum soda can and L01's quiz used foil — a child may name the thing rather than its stuff. Copper, gold, silver, brass and tin are true answers a child may know from home; they are accepted as true, not as synonyms of the lesson's word (the why names the lesson's case). "Metal" and "steel" are not accepted: "metal" is Nora's own word, and steel is the metal a magnet does pull.
Why: Aluminum is a metal too, but it is not steel. / The magnet comes close, and the aluminum can stays where it is. / A magnet does not pull aluminum. / So a magnet does not pull everything made of metal, and Nora is not right.
The second claim of type 6 (FOR3-024), for the generator — not in the file, one exemplar per type:
Stem: Mia says two magnets always stick together. Type what else two magnets can do when they come close.
Accept: push apart · they push apart · they can push apart · push each other apart · they push each other apart · push away · push each other away · they push each other away · push · they push · push apart without touching · they push apart without touching
Why: Two magnets can pull together. / If you turn one magnet around, pull changes to push. / The two magnets push apart, without touching. / So two magnets do not always stick together, and Mia is not right.
Hard because: the student must see that "always stick together" falls to the one other thing two magnets do, recall it, and produce the phrase; "pull together" is what Mia already said, so it is no answer.
History — the MCQ form of type 6 before James's typed-entry ruling (28 Sep 2026, evening), kept so the change is checkable: "Nora says a magnet pulls everything made of metal. Which happening shows that Nora is wrong?" — a) A magnet is held near an aluminum can, and the can stays where it is (key); b) A magnet picks up a steel nail; c) A magnet is held near a wooden block, and the block stays where it is; d) A magnet sticks to a steel door. Its stem carried one negative ("wrong") over four positive options, flagged for James as N7; the typed stem is positive, so N7 is closed.
Reading note — fresh instances
The lessons use a paperclip, a nail, a soup can and a soda can (L01), two magnets in your hand and a nail (L02), a cupboard, pins on a carpet, train cars and a plastic button (L03); the quizzes use spoons, foil, a bottle cap, scissors, a paper plate, pins on a bench, a key ring, a fork, Ana's train cars, Ben's and Priya's and Leo's and Sam's magnets, Zara's toy box, Leo's nails in the grass, Leo's drawing on a wooden door, Mia's fridge and wooden door, Ana's aluminum door, Omar's keys in a puddle; the practice uses a thumbtack, a plastic cup, a bolt, Nina's magnets, Ravi's claim, Dev's bedroom door, Lena's pins in sand, a garden gate (FRQ). Against all of these: PP-1's four things and PP-2's bottle cap on a table are fresh (L01-5's bottle cap asks "does it pull?"; PP-2 asks "what pulled it?" — a different move); PP-3 (Ana's desk magnets) is fresh in scene; PP-4 (Yusuf's shed door) shares the move of PR-8 (Dev's bedroom door) and PR-10 (the garden gate FRQ) with a fresh scene and name — draw-one-per-test with PR-8; PP-5 (Lena's water bottle) is fresh against L03-9 (Ana's aluminum door); PP-6 (toy boats) is fresh against L03's train cars; PP-7 (Nora) re-asks L01-10's claim (Kai) as a TYPED counterexample with a fresh claimant — a different move from the quiz's bare yes / no and from the practice's typed term items (PR-11 asks for the metal a magnet DOES pull; PP-7 asks for one it does not) — and the bank's type 6 draws its claims from the two the sheet names. Nora and Yusuf are not used in Topics 1–4 (they appear in Topic 6; the course reuses one name pool).