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Skill: course-build → write-mcqs → write-explanation, design-check-sequence @ 4a6e93d · typed hard type: write-mcqs @ 11cce8f

Topic 6 — Forces that touch, and forces that don't — the PP100's five question types, with their exemplars

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). This sheet writes the exemplars in full, exactly as they sit in content/G3T06.py (PP100, flagged TYPE_SHEET_ONLY). Five types; types 1, 3 and 5 carry a second form so that every atom and every pair in the coverage table has a type (the non-author review's MUST 2, 28 Sep 2026). No other bank item exists yet. Once the types stand, about fifty items are generated from them, varying scene and nouns, easy-heavy; type 5 — the typed hard type — carries at most eight.

Revised 28 Sep 2026 (night) on James's ruling that hard PP100 items are typed ("PP100s can have text entry or numeric entry… hard questions would be text entry or even numeric entry if it is a numerical question"): the one hard type, type 5, is now TEXT ENTRY. The student types the puller from a scene that never names it — "Earth's pull" for a falling plum, "a magnet" for a steel nut that jumps up to something in a hand. The old type 5 (a claim judged against four happenings, an MCQ) is withdrawn: a claim judged is DOK 3, so it cannot sit in the bank as an MCQ under the ruling, and the practice set's Freya item already carries the topic's claim. Easy and medium types stay four-option MCQs and remain the bulk. The site grades a typed answer exact-match after lower-casing, trimming and dropping a final period; it does not drop articles, so each accept list carries "the X" and "X", and the apostrophe-less "Earths pull" a young typist writes. No accept list carries a word the lesson did not teach.

Revised 28 Sep 2026 (evening) after the non-author review (REVIEW_G3T06_2026-09-28.md): coverage table added; type 1 gains its rubbed-balloon form and type 3 its rubbed-balloon case; the type-3 stem no longer says "pulls" or "this"; every steel object near a magnet is plain steel and none is cutlery (washer, bottle cap); options copied from practice items replaced (a bike; a dog and its bowl; wet / warm the balloon).

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. Easy and medium items are four-option MCQs with a why (no per-option feedback in the bank; the engine prints Correct / Not quite). Hard items are text entry: a stem, an accept list, a why in the lesson's words; the engine prints Correct, or Not quite with the first accepted answer. Tags follow depth of reasoning: easy = one-step sort or the fact; medium = a fresh case that needs two ideas, or the fact applied as an action; hard = two steps and the answer PRODUCED, not picked (the sort first, then the name of the puller). No option bundles a verdict with a reason; every stem is a positive question; no item figure carries an arrow or a verdict; no bank item shows a reference list or the sort card; no magnet item uses cutlery as its steel object (most cutlery is stainless and is not pulled).

The five types

TypeItemsAtomTagThe stem asks…The four options are…Exemplar scenes
1PP-1, PP-2FOR3-020; second form FOR3-027 (the pair 020 + 027)easywhich of four described forces acts without touching (or, the mirror form: which one touches)four short described forces ("a dog pulls on its leash"); exactly one is of the asked kind. In the second form the key is the rubbed balloona leash, a bike, a raindrop, a door · a bike, a rubbed balloon and hair, a wagon, a cat and a door
2PP-3FOR3-027easywhat a light thing does when a RUBBED balloon is held just above or beside itfour happenings: it rises / stays still / slides away / rolls off; the key is the pull toward the balloona feather on a table
3PP-4, PP-5FOR3-026 — the sort's own four-option form (each case pairs it with Topic 5's FOR3-001; the second case pairs it with FOR3-027)mediumwhich kind of force the puller puts on the thing, sorting on two ideas at once (push or pull; touches or doesn't); the stem describes the motion and never says "push" or "pull"the four cells: a push that touches / a pull that touches / a push that doesn't touch / a pull that doesn't toucha magnet and a steel washer · a rubbed balloon and bits of tissue
4PP-6FOR3-027mediuma balloon over light things does nothing: what should the child do so the balloon pulls themfour actions the child could take; only the rub worksAnya and bits of tissue paper
5PP-7, PP-8FOR3-020 + FOR3-026hard · text entrya thing moves and the stem says nothing touched it; the stem never names the puller: what pulls it (or what is the person holding)no options — the student types the puller in the lesson's words: "Earth's pull" / "Earth", or "a magnet"; an accept list of the surface formsa ripe plum falls from a tree · Elias holds something above a steel nut, and the nut jumps up

Coverage (every atom alone, and the pairs)

AtomTypes testing it alonePair types
FOR3-020 some forces act without touching1 (first form), 5 (typed, both forms)1 second form (with 027), 5 (with 026: the student must first see that nothing touched the thing)
FOR3-027 a rubbed balloon pulls without touching2, 41 second form (with 020), 3 second case (with 026)
FOR3-026 the sort3 (its four-option form; each case also draws on Topic 5's push-or-pull, FOR3-001)3 second case (with 027), 5 (with 020, typed)

Order in the file: easy → medium → hard (PP-1 … PP-8). MCQ keys (PP-1 … PP-6): C A A D D B (no letter over 35 %); PP-7 and PP-8 are typed and carry no key letter.

The exemplars, in full

Type 1 — PP-1 · FOR3-020 · easy

Stem: Which of these forces acts without touching?

Why: The dog touches its collar and leash, the girl touches the bike, and the boy touches the door. / Nothing touches the raindrop on its way down. / Earth pulls it down anyway. / Earth's pull is the force that acts without touching.


Type 1, second form — PP-2 · FOR3-027 (+ FOR3-020) · easy

Stem: Which of these forces acts without touching?

Why: The boy touches the bike, the girl touches the wagon's handle, and the cat touches the door. / The rubbed balloon stays a gap away from the girl's hair. / The balloon pulls her hair up anyway. / The rubbed balloon's pull is the force that acts without touching.


Type 2 — PP-3 · FOR3-027 · easy

Stem: A boy rubs a balloon on his hair and holds it just above a small feather on a table. What happens to the feather?

Why: The balloon has been rubbed. / A rubbed balloon pulls light things toward it, without touching them. / A feather is light. / So the feather rises up toward the balloon.


Type 3 — PP-4 · FOR3-026 (+ FOR3-001) · medium

Stem: A magnet is held near a steel washer on a table, and the washer slides toward the magnet. Which kind of force does the magnet put on the washer?

Why: The washer moves toward the magnet, so the magnet pulls it. / There is a gap between the magnet and the washer the whole time. / So the magnet's pull is a pull that doesn't touch.

Medium because: two sorts at once (push or pull from Topic 5, read off the motion; touches or doesn't from this topic), on a fresh scene.


Type 3, second case — PP-5 · FOR3-026 (+ FOR3-027) · medium

Stem: A rubbed balloon is held above bits of tissue, and the bits jump up to it. Which kind of force does the balloon put on the bits?

Why: The bits move toward the balloon, so the balloon pulls them. / There is a gap between the balloon and the bits when they start to move. / So the balloon's pull is a pull that doesn't touch.

Medium because: the same two sorts on the topic's third non-touching force.


Type 4 — PP-6 · FOR3-027 · medium

Stem: Anya holds a balloon above bits of tissue paper, and nothing happens. What should she do so the balloon pulls the bits up?

Why: A balloon that has not been rubbed pulls nothing. / A rubbed balloon pulls light things toward it. / So Anya should rub the balloon on her sweater. / Wetting it, waiting or warming it changes nothing.

Medium because: the fact is applied backwards — the student names the missing step from the outcome, on a fresh scene. Each distractor is a child's guess; none does anything.


Type 5 — PP-7 · FOR3-020 (+ FOR3-026) · hard · text entry

Stem: A ripe plum comes loose from a tree and falls to the grass. Nothing touches the plum on its way down. What pulls the plum down?

Accept (exact match after lower-casing, trimming and dropping a final period): Earth's pull · Earth · the Earth · the Earth's pull · Earths pull · the Earths pull · Earth pulls it · Earth pulls it down · the pull of Earth · the pull of the Earth

Why: Nothing touches the plum on its way down. / Earth pulls it down anyway. / Earth's pull is a force that doesn't touch.

Hard because: the stem never names the puller. The student reasons in two steps — nothing touches the plum, so the force is one of the three that don't touch; it falls down, so the puller is Earth — and PRODUCES the name instead of picking it from four. "Gravity" is not accepted: the course's word for the force is Earth's pull (James, 25 Sep 2026), and a student who types it reads "The answer we were looking for: Earth's pull" and the why.


Type 5, second form — PP-8 · FOR3-020 + FOR3-026 · hard · text entry

Stem: Elias holds something just above a steel nut, and the nut jumps up to it. Nothing touched the nut. What is Elias holding?

Accept: a magnet · magnet · the magnet · a bar magnet · his magnet

Why: Nothing touched the nut, and it still moved. / So the pull on it is a force that doesn't touch. / The nut is steel, and it jumped up to the thing in Elias's hand. / A magnet pulls steel without touching it. / So Elias is holding a magnet.

Hard because: the sort comes first (nothing touched the nut, so the force doesn't touch — FOR3-026), then the name of the puller from what moved (steel jumps up: a magnet's pull — FOR3-020 with Topic 4); the answer is produced and appears nowhere on the page. A rubbed balloon is not a second defensible answer: the lesson teaches that it pulls LIGHT things (hair, paper bits, an empty can), and a steel nut is not one.


Reading notes for the review