Skill: course-build → write-mcqs → write-explanation @ 3a2c39d; v2 @ efd8fba
Topic 24 — question types in the PP100 bank, one exemplar each (2 October 2026, v2 after the reviews)
James reviews a bank as its question TYPES first, one exemplar each (vault: 50 Decisions/A bank is reviewed as its question types first, one exemplar each.md). This sheet lists the eleven types the Grade 4 Topic 24 bank runs on and prints one exemplar per type in full as it ships in content/G4T24_pp100_bank.py. v2 (2 Oct 2026, evening): the blind read, the question review and the figure review applied — every key one clause and never the single longest option (check_key_tells.py: KEY TELLS 0 of 122), every stem a positive question, US words, named farms, the tub model's moves and readings varied, the bank's two drawn items on their own drawings (a grid filled from the other corner; the TUB, not the bowl), two EAR4-058 term recalls added, the cactus-farm item retagged to EAR4-058.
One cluster. The topic is one PP100 cluster of five atoms (EAR4-058 → 059 → 060 → 061 → 062, capstone 062). Items per atom: 14 · 9 · 10 · 11 · 13 = 57. Tiers: 22 easy · 18 medium · 17 hard (6 typed, 1 multi-select, 2 drawn items, 8 four-option MCQs with a "hard because" line each). EAR4-058 carries easy items and its two term recalls (one typed, hard tier); EAR4-059 easy and medium; EAR4-060 and 061 run from easy to hard; EAR4-062, the capstone, medium and hard only. MCQ keys A 10 · B 18 · C 12 · D 10 (50 MCQs).
The bar list (things a generated bank must never use because they break a taught claim or a rule): "gravity" as the puller ("Earth pulls the drops down" is Grade 3's sentence); "the Sun lifts / pulls / sucks the water up" (nothing is lifted: the Sun's light carries energy, the water warms up and evaporates — EAR4-056's cross note); "water is a form of energy" or "the Sun's energy is in the water"; "groundwater", "aquifer", "desalination", "percent" as student words (this topic says "water under the ground", "take the salt out", "of every 100 squares"); "iceberg" or any word no lesson taught as an option; the Great Salt Lake or any salt lake as an instance of "a lake" (the topic's lakes are fresh); a sea fish, seal or sea bird as a living thing that "needs fresh water" (the rule says "on land"; the sea fish is the table's exception row); tasting as an observation (the cup's water is STATED to be fresh, never tasted); "bowl / cup / plastic wrap / bag of ice" as a bank model (the lesson's model; the bank's model is a tub, a jar, a glass lid and a tray of ice cubes, drawn as such); any lesson, quiz, attached or practice scene as a bank scene; "Farm A / Farm B" or any lettered instance; "taps", "washing-up" or any British word; a stem of the form "Which sentence shows he is wrong?" (every stem is a positive question); a key that is the single longest option or the only option with a second clause; "strand"; "biggest / smallest" for a count or a share.
⟂ draw constraints (pairs never served in one PP100 draw: one item states what another asks):
- PP-2 (97 squares are in one place: the ocean) ⟂ PP-1 (what is nearly all of the blue) ⟂ PP-9 (the true sentence about the blue).
- PP-3 (where most fresh water is) ⟂ PP-8 (the frozen water's letter on the grid) ⟂ PP-11 (the true sentence: most fresh water is frozen) — near-duplicates, draw one.
- PP-21 (9 of 10 cups come from one place) ⟂ PP-30 (how many of the 10 cups come from everywhere else) ⟂ PP-42 (type the place most water evaporates from).
- PP-20 (fog's water) ⟂ PP-29 (the true sentence about rain 500 miles from the sea) — one source item per draw; PP-26's stem states the source, so PP-26 is never drawn with either. PP-28 (every lake and river stops evaporating: only a little less rain) ⟂ PP-31 (the ocean stops evaporating: much less rain) — the two stopped-evaporating items, draw one (v3).
- PP-22 (what is left in the salt pans) ⟂ PP-44 (type the white stuff left on the rock) ⟂ PP-36 (which step leaves the salt behind).
- PP-38 (the tub's drops stand for a cloud) ⟂ PP-49 (which letter on the drawn tub stands for a cloud).
- PP-39 (the ice cubes are the solid) ⟂ PP-56 (select every liquid part) — the second's distractors name the first's key.
- PP-37 (the tub's salt water is the ocean) ⟂ PP-52 (type the real thing the warm salt water stands for).
- PP-50 (type the state of the vapor: gas) ⟂ PP-40 (the state of the water in the air under the lid).
- PP-12 (the harbor's water is salt water) ⟂ PP-5 (which of these is salt water); PP-41 (type ice cap) ⟂ PP-7 (the ice of a glacier is the frozen fresh water).
The eleven types
| # | Question type | Exemplar | Items | Count | Hard end |
|---|---|---|---|---|---|
| 1 | Where is it: the place Earth's water, its fresh water or its liquid fresh water sits; fixed set PLACE4 = the ocean / ice caps and glaciers / water under the ground / the rivers and the lakes (v2 wording, lengths equalised). | PP-2 | PP-1–4, PP-13 | 5 | none — easy |
| 2 | Pick the one of four described waters that is salt water / fresh water / frozen fresh water. | PP-5 | PP-5–7 | 3 | none — easy |
| 3 | Read a drawn item (the hundred-squares grid with letters; the ocean-to-rain landscape with letters) and apply a rule to one lettered part. | PP-8 | PP-8, PP-45 | 2 | PP-45 (where the water has just left the salt behind) |
| 4 | A claim fixed as wrong in the stem; a POSITIVE question asks for the true sentence, the amount, the reason or what happens next (v2: no 'shows he is wrong'); or pick the one true sentence of four. | PP-9 | PP-9–11, PP-23, PP-29, PP-35, PP-47–48 | 8 | PP-47, PP-48 (a claim about water leaving the cycle; a half-true claim about two 'different waters') |
| 6 | Why fresh water matters: which living thing needs it, what happens to a plant or a water supply in a dry year, why an island supply still runs short, which use empties a supply fastest (the outcome or the reason). | PP-17 | PP-14–19, PP-24–25 | 8 | none — easy and medium |
| 7 | Where did this water evaporate from (SOURCE4 = the ocean / lakes / rivers / puddles and wet ground) on a fresh scene, or why the ocean sends the most water into the air, or what changes if the ocean stopped evaporating. | PP-26 | PP-20–21, PP-26–28, PP-30–31, PP-43 | 8 | PP-43 (why clouds keep forming year after year) |
| 9 | The salt and the path: what is left when sea water dries, which step leaves the salt, which water the rain is, where a drop was before, how the ocean reaches a lake, the drop's story in order. | PP-33 | PP-22, PP-32–34, PP-36, PP-46 | 6 | PP-46 (four steps in order) |
| 10 | The model: which part stands for which real thing, the state of its water, which step happens at the cold spot — described (the tub model) or drawn (the lettered TUB); the one multi-select (every liquid part). | PP-38 | PP-37–40, PP-49, PP-56–57 | 7 | PP-49 (drawn tub), PP-56 (multi), PP-57 (from the cold spot to its step) |
| 11 | Predict the model under a changed condition: cold water in the shade; the lid left off; where the salt is after two days. | PP-53 | PP-53–55 | 3 | all hard |
| 12 | Type the word: the place (ocean ×2), what is left behind (salt), the state (gas; liquid). | PP-42 | PP-42, PP-44, PP-50–52 | 5 | all hard, all typed |
| 13 | Recall EAR4-058's coined terms: salt water by MCQ, ice cap typed (v2, the review's hard-tier recall rule). | PP-41 | PP-12, PP-41 | 2 | PP-41 (typed) |
(Type numbers 5 and 8 were merged into 4 and 9 during drafting; type 13 was added in v2 for the term recalls.)
The exemplars, in full
Type 1 — PP-2 (easy, EAR4-058). Of every 100 squares of Earth's water, 97 squares are in one place. Which place?
Options: the ocean · ice caps and glaciers · water under the ground · the rivers and the lakes.
Why: Of every 100 squares of Earth's water, 97 are salt water in the ocean. So the place is the ocean.
Type 2 — PP-5 (easy, EAR4-058). Which of these is salt water?
Options: the water in a clear forest river · the ice of a glacier · the water a sea turtle swims in · rain falling on a town.
Why: Salt water is water with salt dissolved in it, and the ocean's water is salt water. A sea turtle swims in the sea. So the water a sea turtle swims in is salt water.
Type 3 — PP-8 (easy, EAR4-058, figure pp_grid_nrmp). The grid shows all of Earth's water as 100 squares. Which letter marks the fresh water that is frozen?
Options: N · R · M · P.
Why: Fresh water that is frozen is 2 of every 100 squares: the ice of the ice caps and glaciers. R marks the 2 white squares. So R marks the frozen fresh water.
Type 4 — PP-9 (easy, EAR4-058). A boy says Earth looks mostly blue from space, so there is plenty of water for everyone to drink. Which sentence is true about the blue water?
Options: It is mostly ice. · It is mostly fresh water in lakes. · It is nearly all salt water. · It is mostly water vapor..
Why: Nearly all of Earth's water is salt water in the ocean. Drinking salt water makes people sick. So the blue is not water people can drink, and the boy is not right.
Type 6 — PP-17 (easy, EAR4-059). Why does the small share of fresh water on Earth matter so much to people?
Options: People and farms can use only fresh water. · Fresh water is heavier than salt water. · Fresh water is the only water that evaporates. · Fresh water is the only water in the ocean..
Why: People, animals and plants on land need fresh water. Only 1 square of every 100 is fresh water we can reach. So the small share of fresh water matters to every person and every farm.
Type 7 — PP-26 (medium, EAR4-060). A heavy rainstorm soaks a prairie 1,000 miles from the sea, yet most of that rain's water evaporated from the ocean. How did the water get so far from the sea?
Options: Rivers carried the water uphill to the prairie. · The wind carried the clouds across the land. · The rain soaked up through the ground from the sea. · The ocean rose over the prairie..
Why: Most of the water in the air evaporated from the ocean. The wind carries water vapor and clouds a long way across the land. So the ocean's water reached the prairie as rain.
Type 9 — PP-33 (medium, EAR4-061). A drop of water in a farm pond fell as rain last night. Where was most of that water before it went into the air?
Options: in the pond all along · under the farm · frozen in a glacier · in the ocean.
Why: Most of the water in the air evaporated from the ocean. Evaporation left the salt behind, and the water fell as rain into the pond. So most of the drop's water was in the ocean.
Type 10 — PP-38 (medium, EAR4-062). After a morning in the sun, the class lifts the lid of the tub model and finds drops hanging under it. Which real thing do those drops stand for?
Options: the ocean · a cloud · a river · a glacier.
Why: A cloud is tiny drops of water that condensed high up where the air is cold. The drops under the lid condensed under the cold spot. So the drops stand for a cloud.
Type 11 — PP-53 (hard, EAR4-062). A tub model is filled with cold salt water instead of warm, and it stands in the shade all morning. What is in the small jar at noon?
Options: a jar full of fresh water · almost nothing · a jar full of salt water · a lump of ice.
Why: The Sun's light warms the water, and warm water evaporates. Cold water in the shade hardly evaporates at all, so almost no vapor condenses and almost nothing drips into the jar. So the jar holds almost nothing.
Type 12 — PP-42 (hard, EAR4-060, typed). Most of the water that goes into Earth's air evaporates from one place. Type the name of that place.
Accept: ocean · the ocean · oceans · the oceans · sea · the sea · the seas · ocean water · sea water.
Why: Most of the water that goes into the air evaporates from the ocean. That is because the ocean is where most of the water is. So the place is the ocean.
Type 13 — PP-41 (hard, EAR4-058, typed). A plane flies over Greenland, far in the north near the North Pole. Below it, ice more than a mile thick covers nearly all the land. Type the two-word name for this ice. (v3: re-scened; v2's stem was PR-15's with the pole swapped.)
Accept: ice cap · an ice cap · the ice cap · ice caps · icecap · ice-cap · the ice caps.
Why: A thick sheet of ice that covers the land near the North Pole or the South Pole has a name. That name is an ice cap.
Design-move inventory (every bank item: the move, the scene kind, the nearest lesson-side instance)
| PP | d | atom | Move | Scene kind | Nearest lesson-side instance |
|---|---|---|---|---|---|
| 1 | e | 058 | name what nearly all the blue is | astronauts over Earth | L01 headache (the globe) — fresh: space |
| 2 | e | 058 | name the place of 97 squares | bare fact | L01 grid |
| 3 | e | 058 | where to go to see most fresh water | a scientist's trip | L01 q5; draw-one with PP-11 |
| 4 | e | 058 | where most LIQUID fresh water is | bare fact | L01 fresh_zoom |
| 5 | e | 058 | pick the salt water of four | forest river, glacier, a sea turtle, rain | L01 table_fresh_salt — new instances |
| 6 | e | 058 | pick the fresh water of four | pelican, sea spray, tide pool, drinking fountain | L01 q2/q3 — new |
| 7 | e | 058 | pick the frozen fresh water (the ice of a glacier; a lake's WATER is the distractor — v2) | lake, glacier, ocean, river | L01 glacier line |
| 8 | e | 058 | read the grid: the frozen water's letter (v2: the bank's grid is filled from the other corner, chips above, letters N R M P) | drawn grid N R M P | L01 q11 asks the reachable fresh water on J K L — different grid, different letter |
| 9 | e | 058 | the true sentence about the blue (v2 positive stem) | a boy, Earth from space | L01 q6 |
| 10 | e | 058 | how much of Earth's water all the rivers hold (v2 positive stem) | the Mississippi | L01 q7 |
| 11 | e | 058 | pick the true sentence | bare | L01 q5 — pick form |
| 12 | e | 058 | recall the coined term salt water (v2, EAR4-058 hard-tier recall by MCQ) | a harbor | L04 q9 / PR-13 — new scene |
| 13 | e | 058 | where a dry-land farm reaches fresh water (v2: retagged 058, easy) | a cactus farm | L01 well photo |
| 14 | e | 059 | which living thing needs fresh water | horse, shark, seal, crab | L02 table_needs — new animals |
| 15 | e | 059 | what salt water does to a crop | a wheat field | L02 corn plant — new crop |
| 16 | e | 059 | what happens to a rain-fed supply in a dry summer | a village's small river | L02 reservoir — new supply kind |
| 17 | e | 059 | why the small share matters | bare reason | L02 rule |
| 18 | e | 059 | why sea water cannot be drunk | a lighthouse keeper | L02 camping item (q7) |
| 19 | e | 059 | why a pond gets lower | a horse ranch | L02 q3/q4 — new supply |
| 20 | e | 060 | where fog's water evaporated from (v2: 'from the sea' cut from the stem) | fog over a hilly city | L03 — fog is new |
| 21 | e | 060 | the place of 9 of 10 cups | bare | L03 q3 — asks the place |
| 22 | e | 061 | what is left when sea water dries in pans (v2: salt pans, not a kettle — PR-10 boils a pot) | salt pans by the sea | L04 dish — new surface |
| 23 | m | 059 | why an island hotel still needs to save water (v2 positive stem) | an island hotel | L02 q5 |
| 24 | m | 059 | which pond runs short first (v2: a dairy farm and a vegetable farm) | two named farms | L02 — comparative |
| 25 | m | 059 | which use empties a supply fastest (v2: faucet, dishwater) | a town's pools | L02 q9 |
| 26 | m | 060 | how ocean water reaches a far place | a prairie storm | L03 wind line |
| 27 | m | 060 | why the ocean sends the most water | bare reason | L03 q9 |
| 28 | m | 060 | predict if every lake and river stopped evaporating: only a little less rain (v3; was dew's source, one move with PP-20) | thought experiment | PP-31's mirror — the other 1 cup |
| 29 | m | 060 | the true sentence about rain 500 miles from the sea (v2 positive stem) | a boy's town | L03 q8 |
| 30 | m | 060 | how many cups from everywhere else | bare | L03 q3 — the other reading |
| 31 | m | 060 | predict if the ocean stopped evaporating | thought experiment | new |
| 32 | m | 061 | which water rain at sea is | a sailboat | L04 video question — at sea |
| 33 | m | 061 | where a pond drop was before it went into the air | a farm pond | L04 q6 — new water body |
| 34 | m | 061 | how the ocean's water reaches a mid-country lake (v2 positive stem) | a lake mid-country | L04 rule |
| 35 | m | 061 | why a rain barrel's water is fresh (v2 positive stem) | a rain barrel | L04 q5 |
| 36 | m | 061 | which step leaves the salt | bare STEP4 | L04 why item |
| 37 | m | 062 | which tub part is the ocean | the tub model, set up | L05 q2 (Levi's pan) |
| 38 | m | 062 | what the lid's drops stand for (v2: the class lifts the lid after a morning) | the tub model | L05 table_model_real |
| 39 | m | 062 | which tub part is the solid (v2: moved to a shady shelf) | the tub model | L05 q7 |
| 40 | m | 062 | the state of the water in the air under the lid (v2: asks the state, not the place) | the tub model | L05 q3 |
| 41 | h | 058 | TYPE the coined term ice cap (v2, EAR4-058) | the North Pole | PR-15 — the South Pole there |
| 42 | h | 060 | TYPE the place | bare | L03 rule |
| 43 | h | 060 | why clouds keep forming | bare chain | L03 — new chain |
| 44 | h | 061 | TYPE what is left | sea water on a flat rock | L04 dish — new surface |
| 45 | h | 061 | read the landscape: where the water has just left the salt behind (v2 stem) | drawn N P R Q | L04 ocean_rain_labels — item form |
| 46 | h | 061 | the drop's story in order (v2: four steps in every option) | a canal | L04 — ordering |
| 47 | h | 061 | what happens next to a town's used river water (v2 positive stem) | a town's river water | new |
| 48 | h | 061 | how rain water and sea water are connected (v2 positive stem) | bare claim | L04 q8 |
| 49 | h | 062 | read the drawn TUB model: the cloud's letter (v2: a tub, a jar, a flat lid, four cubes, three drops; letters Q P R N) | drawn tub Q P R N | L05 q9 / PR-11 use the BOWL on J K L M / S T U V |
| 50 | h | 062 | TYPE the vapor's state | model | L05 q3 |
| 51 | h | 062 | TYPE the drops' state | model | L05 states run |
| 52 | h | 062 | TYPE the real thing for the warm salt water | model | L05 video question |
| 53 | h | 062 | predict: cold water, shade, a morning (v2 reading) | the tub model | L05 q10 (dark cupboard) |
| 54 | h | 062 | predict: lid off | the tub model | new |
| 55 | h | 062 | track the salt after two days, a spoonful collected (v2 reading) | the tub model | L05 q12 |
| 56 | h | 062 | select every liquid part (multi) | the tub model | L05 states run |
| 57 | h | 062 | step fastest at the cold spot | the tub model | L05 q4 |
Lettered renders: pp_grid_nrmp (N, R, M, P; the grid filled from the top-left corner, chips above the three squares, the whole-grid line along the bottom) — PP-8 only; pp_ocean_rain_nprq (N on the ocean, P on the dots, R on the rain, Q on the lake) — PP-45 only; pp_tub_qprn (the TUB: Q on the dots, P leadered to a drop, R above the tray of four cubes, N on the water) — PP-49 only; the quizzes use q_grid_jkl (J, K, L) and q_model_jklm (J, K, L, M); the practice uses pr_model_stuv (S, T, U, V). No lettered render is shared between the quizzes, the practice set and the bank; no letters A–D. The counts on every grid stay 97 / 2 / 1: they are the data.