Skill: write-like-james @ cca3af6 · the build: write-lesson, write-mcqs, write-video-script, write-summary, write-intro @ c83cbd2; the non-author review (review-lesson Role B and C, review-questions, review-figures, review-accuracy, review-physics) applied @ cca3af6; the blind read of the re-cut bundle is next
Topic 2 "What unequal forces do to motion" — your read (8 October 2026)
Skim first
The lessons in teaching order, each with its one rule sentence; then the intro script; then the question types. The review page follows.
The lessons and their rules
| Lesson | Atom | Rule sentence |
|---|---|---|
| L01 Equal or unequal? Read the force arrows | FOR5-022 | The same length means equal forces. Different lengths mean unequal forces. Equal forces are balanced forces. Unequal forces are unbalanced forces. |
| L02 Predict how the motion changes when the forces are unequal | FOR5-023 | Stronger force the same way: it speeds up. Stronger force against the motion: it slows down. A side push, nothing back: it changes direction. A bigger difference makes a bigger change. |
| L03 The same push on more mass makes a smaller change | FOR5-041 | The same force on more mass makes a smaller change. A stronger force makes a bigger change. More mass makes a smaller change. |
The intro script (120 words, about 60 s)
Here's Miss Baptiste's class at field day. Two teams pull on a long rope, and a strip of cloth tied to its middle hangs over the chalk line. Both teams pull as hard as they can, but the cloth doesn't move. Then it starts to move toward one team, slowly at first, then faster and faster. Both teams pulled the whole time. So what changed, and how could a drawing show it? To find out, we will look at drawings of pushes and pulls, what happens when one force is stronger, and what the same push does to a light thing and a heavy thing. Okay, so are you ready to find out what happens when one force is stronger?
The question types (from TYPES_G5T02.md)
- Type 1 (easy (one hard) · MCQ, the verdict set · 022): from two arrow lengths (text or drawn), which statement about the forces is true — The forces are equal. / unequal: X is stronger / unequal: Y is stronger / Only one force acts on it. (the hard one: both pairs of a four-force description)
- Type 2 (easy · MCQ · 022): what a longer arrow shows; what two arrows of the same length tell you — a stronger force / lasts longer / a heavier part / faster; the same strength / the same time / different objects / both pushes
- Type 3 (medium · MCQ, drawn four-force diagram, the pairs set · 022): which pair of opposite forces is unequal (or equal) — the up and down pair / the left and right pair / both pairs / neither pair
- Type 4 (easy · MCQ · 022): the other name for unequal (balanced) forces — balanced forces / unbalanced forces / contact forces / weight
- Type 5 (easy · MCQ, the four changes · 023): what happens to the motion when the stronger force's direction is given in words — speeds up / slows down / changes direction / keeps the same speed
- Type 6 (medium (one hard) · MCQ, the four changes, drawn or described with a MOVING cue · 023): what happens to the motion, read off two arrows and the direction already moving — the four changes
- Type 7 (medium, hard · typed numeric, drawn · 022, 023): the stronger arrow's length (medium); the difference between the two arrows, after finding the unequal pair or reading both arrows (hard); MCQ: which of two speeds up more — a number of squares, with its word forms; X / Y / both the same / neither moves
- Type 8 (medium, hard · MCQ, reasons · 022, 023, 041): "X is wrong: what is the correct reason?" on a documented belief, or the correct reason for a stated outcome — four single-statement reasons
- Type 9 (easy, medium, hard · MCQ, the compare set · 041): which of two objects, same force, changes its motion more or less — the empty one / the full one / both the same / neither one moves
- Type 10 (medium · MCQ, reasons · 041): why the full one speeds up less; what is different about the loaded chair — It has more mass. / Earth pins it down / a weaker push / bigger outside; more mass / weaker push / Earth pulls sideways / smoother wheels
- Type 11 (easy · MCQ · 041): which has more mass — the full can / the empty can / the same / neither
- Type 12 (medium, hard · MCQ, chains · 023, 041): what he must do to match the empty one's change; a steady cart rolls onto carpet; a gentle push on the loaded trailer against a stronger push on the empty one — push harder / just as hard / more gently / sit lower; the four changes; the stronger push on the empty trailer / …
- Type 13 (hard · typed text · 041): the science word for how much stuff is in a thing, on a scene where the full one speeds up less (the 8 Oct review closed the stem: "what the full one has more of" had "weight" as a true answer) — mass, the mass, more mass, its mass, mas
Three lessons for three atoms, in Miss Baptiste's class with Bodhi, Caleb and Celia.
Bodhi and his dog pull a rope toy, and the two pulls are drawn as arrows on squares the child counts: 4 against 4 is equal forces, 6 against 4 is unequal forces, and L01 says out loud that these are the balanced and unbalanced forces Grade 3 taught.
Caleb pulls a sled at a steady speed, then harder, then gently, and Celia pushes it from the side: L02 finds the stronger force, reads its direction against the way the sled is already moving, and the sled speeds up, slows down or changes direction; the bigger the difference between the arrows, the bigger the change.
Celia pushes an empty wagon and then the same wagon loaded with soil, just as hard: L03 shows the loaded wagon has more mass, so the same push makes a smaller change, and meets the two beliefs the register names (the same push moves everything the same; heavy things are pinned down by Earth's pull).
Forces carry your 8 October names throughout: weight, a contact force, friction; "gravity" is never a force's name.
The non-author review found three things that had to change (a bank explanation naming a bike that was not there; two typed items where "weight" was a right answer marked wrong) and thirteen worth changing; all are applied, every gate is back at its stated result, and the bundle is re-cut for the two cold readers. Pictures are placeholders until the picture pass.
The lessons
Also on the site
Topic intro and poll · summary and three questions · mixed practice · the PP100 bank · the type sheet · the review record
What the review found, and what changed
The non-author review (8 October): 3 must-fix, 13 worth fixing, all applied
Must-fix: a bank why on a boy on roller skates said "the bike slows down" (now "the boy"); two typed items asked for "the word for what the full cooler has more of" — the full cooler has more weight too, so "weight" was a true answer marked wrong; both stems now close to "the science word for how much stuff is in a thing", and the cooler became a toolbox so the cooler-reason MCQ's key no longer hands the word over.
Worth fixing: on seven teaching figures the verdict chip sat above the article's own question line, so the page answered before it asked — the question line now comes first and the figure is the reveal; L02 named friction before its recall line (swapped); L03's opening now asks "Is she right?" after Celia's claim; one vague line ("more mass for that push to get moving") rewritten; a hanging bucket and a hanging sign drawn with unequal forces now read "being pulled up"; a quiz why item that repeated the previous item's claim on the same laundry basket moved to a bag of dog food; a practice item that restated the previous drawn skateboard moved to a tricycle; the summary's rowboat (two rowboats in the bank) became a raft; two gates in the bank became a sofa and a gate; the bank's crate-of-bricks pair, a copy of L03's attached cart-of-bricks question, became a duffel bag; "a moving crate" became "a moving object"; the trunk item's key is now the reason the trunk is hard to move (more mass) rather than a true side-statement; the foam-ball item asks about the same push, not "the same throw as it leaves her hand"; three pair-figure stems stopped saying what the figure shows.
Left as simplifications, on the record: the side push with "nothing pushes back against it" (Grade 3's rule sentence); "the engine's push" on a car; friction held constant as the pull changes; two placements of the object's name across two drawers.
Gates after the fixes: checker 0 FAIL (S46 hits {}, B = 0); terms no hits; articles 0 FAIL; key tells 0 of 102; svg ids PASS; shared checker 0 FAIL, S118 0 FAIL; bundle re-cut (93 MCQ, 6 typed, 1 written; 100 held); batch rebuilt and check_brief.py clean; not sent.
The bank, in brief
50 items in content/G5T02_pp100_bank.py: 44 four-option MCQs, 4 numeric readings and differences off drawn force diagrams, 2 typed words (mass). Per atom: FOR5-022 17 · FOR5-023 17 · FOR5-041 16. Easy 18, medium 20, hard 12, sorted easy to hard and rising with the atom's place. MCQ keys A 14 · B 15 · C 10 · D 5. Thirteen question types, one exemplar each on the type sheet: the two-arrow verdict set (text or drawn); what a longer arrow shows; which pair of four arrows is unequal; the other name for balanced / unbalanced; the four changes from a direction given in words, or read off a drawing with a MOVING cue; the stronger arrow's length typed, and the difference typed after finding the unequal pair; "X is wrong: what is the correct reason?" on the register's beliefs; which of two objects changes more or less for the same force; why the full one speeds up less; which has more mass; two-step chains (push harder to match; steady cart onto carpet; a gentle push on a loaded trailer against a stronger push on the empty one; a heavy ball slowing less); the word mass produced.
Questions for James
none