Skill: course-build → write-mcqs → write-explanation, design-check-sequence @ efd8fba
Topic 38 — What happens when a place changes — the PP100's question types, with their exemplars (v1, 2 October 2026)
What this page is. James reads a bank as its question TYPES first (vault: A bank is reviewed as its question types first, one exemplar each). Under the Grade 4 standing brief the bank is built straight away (51 items in content/G4T38_pp100_bank.py); this sheet is the way in. Each type line says what the stem asks, what the four options (or the accept list) are, and prints one exemplar in full. Tags follow depth of reasoning — easy = one fact or a one-step read; medium = the rule applied to a fresh case, a reason picked, or a drawn cliff read; hard = two ideas chained, a claim judged by its correct reason, a term recalled from a fresh description with no cue word, or a word produced — and rise with the atom's order: LIF4-045 (the same winter, place to place) carries easy and medium only; LIF4-050 (fossils tell the past) runs easy to hard; LIF4-051 (extinct) runs easy to hard; LIF4-052 (the capstone) carries medium and hard only. Every hard item carries a one-line "hard because" (hb) in the bank file.
Rulings already applied. Four options on every MCQ (four fixed sets: the winter-climate set "cold, snowy winters / mild winters / hot, dry summers / rainy summers"; the what-the-place-was set "under the sea / damp and shady / a dry desert / cold, with snow"; the four sisters "extinct / rare / migrating / hibernating"; the outcome set "The kind lives on there. / The kind moves to a place near that suits it. / The kind is extinct. / The kind grows new features to fit."); a fixed set's longest member is whitelisted from the length check by name (the same words sit under every item of its run: PP-4 and PP-7 on the climate set, PP-33 and PP-38 on the outcome set); no option bundles a verdict with its reason (every claim is "X is wrong … What is the correct reason?" with four single-statement reasons); every stem is a positive question of at most two sentences unless tagged hard (S23); an item cliff carries no number chips and its blind text is Topic 21's data line (the bands top to bottom, colour and contents); the stem's layer sentence and the drawing are built from ONE list (ITEM_CLIFFS, bottom to top; cliff_words()); "extinct" and "adapted" are recalled by MCQ among their sisters (RECALL_BY_MCQ, the brief's call for this topic); the typed keys are "water" (closed by the author's note: a fish can stay alive only in water; sea, ocean, lake and river accepted) and "fossils" (a lexicon word); no multi-select; every item names ONE atom; US spelling; units as words. MCQ keys A 12 · B 13 · C 13 · D 11.
The bar list (real things a generated item must never use): any mechanism word (natural selection, evolve, evolution, survival of the fittest: grade 6-8's); "adapt" as a verb a kind performs ("the kind adapts", "adapted itself") — "adapted" is a describing word only; "decide", "learn", "try", "want", "plan" as what a kind does, except inside a claim the key refuses; a cause of the ice age or its ending; hunting as the cause of any kind's dying out (nothing frightening; the register's "place changes" is the cause this topic teaches); birds as living dinosaurs; any lesson scene (Valeria's two grandmas, the Minnesota / Florida January, the Texas hill with sea shells, the Pennsylvania fern, the Montana alligator bones, the Kansas two-layer cliff, the museum and its mammoth skeleton, the dinosaurs as a worked case, the passenger pigeon, the bald eagle, the horseshoe crab, the Minnesota grassland with mammoths, musk oxen and bison; the intro's video call); any quiz scene (Vermont maples and frog, North Dakota pond, southern Texas trees, southern Louisiana butterfly, Georgia and Michigan apple trees, South Carolina live oaks and Maine maples, the Ohio sea star, New Mexico moss, Wyoming palms, the Colorado mountain fish, the Alabama sea turtle, the Carolina parakeet, polar bear, red wolf, great auk, penguins, Florida alligators, the Costa Rica frog, the beaver, the desert lizard, the cold-lake fish, the pine-seed bird, the snail's valley, the seed-eating bird's beak, the cool-forest deer, the goose, the shaded-stream frog, the arctic fox); any practice scene (Indiana bats, the Arizona footprint, the filled-in pond's snails, Seattle, southern Georgia and Alaska towns, the Oklahoma sea urchin, the Nebraska cliff, the Florida panther, the woolly rhino, the salamander, the crow, the turtle's lake, the pale lizard, the parrot); a claim-maker from another topic's row (only Kayla, Travis and Valeria — Tori renamed Kayla in v2); a non-US animal as the example of a kind (penguins and the Costa Rica frog appear only where "far away" is the point); "biggest / smallest" for a count or a distance.
The fifteen types
| Type | Items | Atom | Tags | Form | The stem asks… | The options / the accept | Exemplar scene |
|---|---|---|---|---|---|---|---|
| 1 | 4 | 045 | easy | MCQ | given a place's winter climate, what a named living thing looks like or does in January | four states of that thing (bare / green / in flower / in fruit; frozen / open / dried / snowed; in its burrow / running / eating / swimming) | a Wisconsin oak; a southern California lake; an Idaho ground squirrel; a Tucson hummingbird |
| 2 | 3 | 045 | easy | MCQ, the climate set | given a January scene (or asked which kind of place has one), which winter climate the place has | cold, snowy winters / mild winters / hot, dry summers / rainy summers | a Hawaii yard; a Montana town; bare trees and frozen ponds |
| 3 | 4 | 045 | easy, medium | MCQ | which of two places has the milder winter from its trees; which tree flowers first and why; which class counts more butterflies; why frogs lay eggs two months apart | two places + both the same + cannot tell; four single-statement reasons | a magnolia and a birch; cherry trees in South Carolina and Wisconsin; frogs in Alabama and Wisconsin; Colorado and Alabama classes |
| 4 | 3 | 045, 050 | easy, medium | MCQ | the correct reason robins stay in Mississippi; which fossil shows a place was under the sea / damp and shady | four single-statement reasons; four fossils | Montana and Mississippi robins; a sea shell among land fossils; a fern print among sea fossils |
| 5 | 3 | 050 | easy | MCQ, the what-the-place-was set | given a fossil and where its kind can stay alive, what the place was like back then | under the sea / damp and shady / a dry desert / cold, with snow | an Iowa clam; a Utah fern; Indiana coral |
| 6 | 5 | 050 | medium, hard | MCQ | what a fossil tells about a place (and what has changed since); two fossils in one layer read together | four single statements | Alaska palms; Tennessee shark teeth; South Dakota tropical leaves; a Nevada freshwater fish; Missouri clams and sharks |
| 7 | 2 | 050 | medium | MCQ, drawn cliff | from a drawn cliff, what the place was like first and later | four orders | a fern print, sand, shells; shells, sand, tree roots |
| 8 | 1 | 050 | hard | typed | the one thing a fish can stay alive only in, which the place had back then | water, the water, sea, the sea, ocean, lake, river, sea water, salt water, fresh water, under water, watter, warter, wter, watr | an Arizona desert fish |
| 9 | 6 | 051 | easy, medium | MCQ, the four sisters | given the evidence (no living one anywhere / a few hundred alive / none seen since a date), what the kind is | extinct / rare / migrating / hibernating; or four "It is …" statements; or four described kinds | the mastodon; the California condor; a beetle; the giant ground sloth; the heath hen; four described kinds |
| 10 | 6 | 051 | medium, hard | MCQ | a named child's claim is wrong (extinct means rare; extinct because none live here; every fossil kind is dead; people and dinosaurs together): what is the correct reason; which is true of a fossil kind still alive | four single-statement reasons; four "It is …" statements | whooping cranes; redwoods; sea otters; the Labrador duck; Stegosaurus; a fish caught off Africa |
| 11 | 1 | 051 | hard | typed | what an extinct kind is known from | fossils, fossil, a fossil, its fossils, bones, its bones, fossil bones, bones and tusks, a skeleton, skeletons, fossel, fosils, fossills | the dire wolf |
| 12 | 7 | 052 | medium, hard | MCQ, the outcome set | given a kind's features, the change, and whether a place near still suits it, what happens to the kind | The kind lives on there. / The kind moves to a place near that suits it. / The kind is extinct. / The kind grows new features to fit. | a cold-water trout; a seed-eating mouse; a dry-valley cactus; an old-pine owl; a fish-eating seal; a one-plant butterfly; a thick-furred mountain rabbit |
| 13 | 3 | 052 | hard | MCQ | two kinds judged against one change; one pond's frogs against the whole kind; a real past change (the ice over Wisconsin) read as the move branch | four paired or single statements | a marsh with a tiny fish and a seed-eating bird; frogs in hundreds of Georgia ponds; the caribou |
| 14 | 2 | 052 | hard | MCQ | a claim judged by its correct reason (a kind changes by trying or learning); the correct reason a kind lives on far to the south | four single-statement reasons | a damp-ground toad; a grass-eating antelope |
| 15 | 1 | 052 | hard | MCQ keyed on the term | the word for a kind whose features suit its place, from a fresh description with no cue word | extinct / dormant / migrating / adapted | the kangaroo rat |
Hard because — type 8 and 11: the word is produced, not picked. Type 6's Missouri layer: two fossils read together as one time and one place. Type 10's hard items: each claim is judged by its correct reason, which needs two words told apart (rare / extinct), two times put in order (dinosaurs / people), or two facts chained (old fossils / living ones caught today); every distractor half-accepts the belief, so the key is not the odd one out. Type 12's rabbit: the place near seems to suit the kind but has no food, so the move branch fails. Type 13: two kinds against one change; the EVERY in "every one has died" against one pond; a real change with the extinct verdict refused. Type 14: the belief judged by its reason; the move branch read as the place that still suits. Type 15: no cue word.
One exemplar per type, in full
Type 1 (easy, LIF4-045). Wisconsin has cold, snowy winters. In January, what does an oak tree in Wisconsin most likely look like? — bare, with no leaves / green, with every leaf / covered in flowers / full of ripe acorns. Why: In a cold-winter place, trees drop every leaf in the fall. Wisconsin's winters are cold and snowy. So in January the oak is bare, with no leaves. (nearest lesson-side instance: L01's attached question, the Vermont maples, two options — here four states of an oak)
Type 2 (easy, LIF4-045). In January, a yard in Hawaii has green trees, flowers in bloom and butterflies. Which winter climate does Hawaii have? — cold, snowy winters / mild winters / hot, dry summers / rainy summers. (nearest: L01-q4, southern Texas's mild winter given and the trees asked — here the scene is given and the climate asked)
Type 3 (medium, LIF4-045). A cherry tree in South Carolina flowers in March, and a cherry tree in Wisconsin flowers in May. What is the correct reason? — Spring comes earlier to the warmer place. / The Wisconsin tree is a younger tree. / Cherry trees in Wisconsin never flower at all. / The South Carolina tree gets much more rain. (nearest: L01-q8, which apple tree flowers first — here the outcome is given and the reason asked)
Type 4 (medium, LIF4-045). Robins fly south from Montana in the fall, but robins in Mississippi stay all winter. What is the correct reason? — Mississippi's mild winter leaves food for the robins. / Mississippi's robins have much thicker feathers than Montana's. / Montana's robins like to travel long distances every year. / Mississippi has no winter at all, only a long summer. (nearest: L01-q10, why two trees' winters differ — here the same kind of bird in two places)
Type 5 (easy, LIF4-050). A clam fossil is found in rock in Iowa, and a clam like it can stay alive only under the sea. What was Iowa like back then? — under the sea / damp and shady / a dry desert / cold, with snow. (nearest: L02-q4, the Ohio sea star, three options — here the four-place set)
Type 6 (hard, LIF4-050). In one rock layer in Missouri, fossils of clams and fossils of sharks sit side by side. Clams of this kind and sharks can stay alive only in the sea. What does the layer tell us? — Sharks once lived on dry land, beside the clams. / The place was under the sea when the layer formed. / The place was under the sea first, then a dry desert. / The clams in the layer ate the sharks. (hard because: two fossils in one layer are read together as one time and one place; nearest: L02's Kansas cliff, two layers — here one layer, two kinds)
Type 7 (medium, LIF4-050, drawn). [cliff: a fern print in the bottom layer; plain tan sand with no fossils in the layer above it; sea shells in the top layer] In this cliff, a fern print sits in the bottom layer; plain tan sand with no fossils sits in the layer above it; sea shells sit in the top layer. What was this place like first, and what was it like later? — damp and shady first, then under the sea / under the sea first, then damp and shady / a desert first, then under the sea / under the sea the whole time. Blind text: cliff with 3 flat layers, top to bottom: cream shell rock with sea shells; tan sand; gray mud with a fern print. (nearest: L02-q7, shells below tree roots in two layers — here three layers, the order reversed, a plain band between)
Type 8 (hard, LIF4-050, typed). A fish fossil is found in rock in a dry desert in Arizona. A fish can stay alive only in one thing, so that place had it back then. Type the name of that thing. — accept: water, the water, sea, the sea, ocean, the ocean, sea water, seawater, salt water, fresh water, a lake, lake, a river, river, a sea, an ocean, under water, underwater, watter, warter, wter, watr. Wrong-answer lines for sand, rock, air. (hard because: the word is produced; closed by the author's note, S30-INFO)
Type 9 (medium, LIF4-051). No living giant ground sloth, an animal as big as a car, has been seen anywhere for about ten thousand years. Which is true of this kind? — It is rare. / It is hibernating. / It lives far away. / It is extinct. (nearest: L03-q10, the Costa Rica frog, two options — here four, with "lives far away" as the catalogued belief)
Type 10 (hard, LIF4-051). The Labrador duck has not been seen alive anywhere since 1878. Travis says it is only rare. Travis is wrong. What is the correct reason? — A kind of duck can never be called rare, only common. / No living Labrador duck is left anywhere on Earth. / Rare and extinct mean exactly the same thing in science. / Every kind of duck comes back again in spring, like geese. (hard because: the belief that extinct means rare is judged by its reason, which needs the two words told apart; nearest: L03-q4, the red wolf, a bare yes / no)
Type 11 (hard, LIF4-051, typed). The dire wolf is extinct. Today we know what a dire wolf looked like only from one kind of thing, dug out of the ground. Type the name of that kind of thing. — accept: fossils, fossil, a fossil, its fossils, the fossils, fossil bones, bones, its bones, the bones, bones and tusks, a skeleton, skeletons, skeleton, fossel, fossels, fosils, fosil, fossills, fosills. Wrong-answer lines for pictures, photos, zoos. (hard because: the word is produced; "fossils" is a lexicon word)
Type 12 (medium, LIF4-052). A kind of trout can stay alive only in cold water, and over many years its river warms up, but a cold stream flows into the river nearby. What happens to the kind? — The kind lives on there. / The kind moves to a place near that suits it. / The kind is extinct. / The kind grows new features to fit. (nearest: L04-q5, the pine-seed bird's move, three options — here the four-outcome set with the Lamarckian distractor)
Type 13 (hard, LIF4-052). A kind of frog lives in hundreds of ponds across the state of Georgia. One pond dries up, and the frogs in it die. Which is true of the kind? — The kind is extinct. / The kind lives on. / The kind is extinct in Georgia. / The kind moves to the sea. (hard because: the extinct verdict needs EVERY one of the kind gone, and one pond's frogs are not the kind; no lesson-side instance — the quiz's predictions all give a kind that lives in one place only)
Type 14 (hard, LIF4-052). Over many years a valley grows too dry for a kind of toad that needs damp ground, and the toad kind becomes extinct. Travis says the toads should have learned to live without damp ground. Travis is wrong. What is the correct reason? — Toads are too small to learn. / The toads had too little time to learn. / A kind cannot change its features by trying. / Toads can live on dry ground if they try hard. (hard because: the belief is judged by its reason; nearest: L04-q7, the seed-eating bird's beak, a bare yes / no)
Type 15 (hard, LIF4-052, keyed on the term). The kangaroo rat of the Arizona desert never drinks: it gets all its water from the seeds it eats. Which word says this about the kangaroo rat and the desert? — extinct / dormant / migrating / adapted. (hard because: the term is recalled from a fresh description with no cue word; nearest: L04-q11, the arctic fox, whose stem says "suit")
Draw constraints (⟂ pairs — never on one test together)
- PP-14 (the mastodon, extinct) ⟂ PP-41 (the dire wolf, typed "fossils"): the first prints "extinct" as a key beside a ten-thousand-years case; a reader who meets both sees the pair's shape.
- PP-9 / PP-11 (clam, coral → under the sea) ⟂ PP-12 (which fossil shows under the sea): PP-12's key "a sea shell" is the datum PP-9 and PP-11 state.
- PP-22 ⟂ PP-23 (the two drawn cliffs): both print "under the sea first" or "damp and shady first" among the orders; one per test.
- PP-33 / PP-38 (the move branch, trout and butterfly) ⟂ PP-45 (the rabbit, whose move branch fails): the pair teaches the trick.
- PP-42 (Labrador duck) ⟂ PP-15 (California condor, rare): PP-42's distractor "Rare and extinct mean exactly the same thing" is PP-15's lesson.
Design-move inventory (one line per bank item; the move, the scene kind, the nearest earlier item)
| PP | Move | Scene kind | Nearest earlier item |
|---|---|---|---|
| 1 | climate given → tree's January state | a northern oak in winter | L01-V (Vermont maples): same move, four states, a different tree and state |
| 2 | climate given → lake's January state | a southern lake in winter | L01-q3 (North Dakota pond, frozen): the mild side of the pair |
| 3 | scene given → climate | an island yard in January | L01-q4 reversed |
| 4 | scene given → climate | a mountain town in January | PP-3's cold twin |
| 5 | climate given → animal's January state | a hibernating ground squirrel | L01-q5 (Vermont frog): a different animal, four states |
| 6 | climate given → animal's January state | a desert hummingbird | L01-q6 (Louisiana butterfly): a different animal, four states |
| 7 | scene → kind of place | bare trees, frozen ponds | PP-3 / PP-4 with the ask reversed |
| 8 | two trees → milder winter | a magnolia and a birch | L01-q10 (live oaks and maples, the reason asked) |
| 9 | fossil + need → the past | a clam in Iowa | L02-q4 (Ohio sea star) |
| 10 | fossil + need → the past | a fern in dry Utah | L02-q5 (New Mexico moss): a plant in a dry place |
| 11 | fossil (need implied) → the past | coral in Indiana | PP-9 with the need implied |
| 12 | which fossil → under the sea | four fossils | NEW (pick the fossil, not the place) |
| 13 | which fossil → damp and shady | four fossils | PP-12's twin |
| 14 | evidence → the four sisters | the mastodon | L03-q1 (Carolina parakeet), two options |
| 15 | evidence → the four sisters | the California condor, rare | L03-q4 (red wolf) |
| 16 | evidence → the four sisters | a forest beetle | L03-q10 (Costa Rica frog) |
| 17 | two flowering dates → the reason | cherry trees | L01-q8 (apple trees, which first) |
| 18 | two egg-laying dates → the reason | frogs in two states | PP-17 on an animal's life cycle |
| 19 | same bird, two places → the reason | robins | L01-q9 (where a goose spends January) |
| 20 | two classes count butterflies → which higher | a school garden count | L01-q6 (one butterfly, yes / no) |
| 21 | fossil in a cold place → what it tells | Alaska palms | L02-q6 (Wyoming palms): here the "tells us" form with the carried-there distractor |
| 22 | drawn cliff → first and later | fern, sand, shells | L02-q7 (shells, roots) |
| 23 | drawn cliff → first and later | shells, sand, roots | PP-22 reversed with a plain band |
| 24 | fossil high in mountains → what it tells | Tennessee shark teeth | L02-q9 (Colorado mountain fish, a claim) |
| 25 | fossil + need → what changed since | South Dakota tropical leaves | NEW (the change since, not the past) |
| 26 | freshwater fossil in a desert → what it tells | a Nevada fish | L02-V (Nevada fish fossil, two options): here four statements including "always a desert" |
| 27 | rare kind called extinct → the reason | whooping cranes | L03-q4 (red wolf) as a reason item |
| 28 | evidence → "It is …" | the giant ground sloth | PP-14 in the statement form |
| 29 | four described kinds → which is extinct | abstract kinds | NEW (the definition applied across four) |
| 30 | evidence with a date → "It is …" | the heath hen | L03-q5 (great auk) |
| 31 | old fossils + living ones → not extinct | redwoods | L03-q8 (Florida alligators, a TRUE claim) |
| 32 | once rare, now many → the reason | sea otters | L03's bald eagle lines (the lesson's near miss, as a reason item) |
| 33 | features + change + place near → outcome | a cold-water trout | L04-q5 (pine-seed bird) |
| 34 | features + change → lives on | a seed-eating mouse | L04-q3 (desert lizard) |
| 35 | features + change + no place near → extinct | a dry-valley cactus | L04-q4 (cold-lake fish) |
| 36 | features + change + no place near → extinct | an old-pine owl | PP-35 on an animal that needs a nest site |
| 37 | features + small change → lives on | a fish-eating seal | PP-34 at sea |
| 38 | features + change + place near → outcome | a one-plant butterfly | PP-33 on a plant need |
| 39 | typed: the need → what the place had | an Arizona desert fish | L02-V in the produced form |
| 40 | two fossils in one layer → one verdict | Missouri clams and sharks | NEW |
| 41 | typed: what an extinct kind is known from | the dire wolf | L03's "known only from its fossils" line |
| 42 | extinct called rare → the reason | the Labrador duck | PP-27 reversed (the kind IS extinct) |
| 43 | people and dinosaurs → the reason | Stegosaurus | L03-q9 (Tyrannosaurus, yes / no) |
| 44 | old fossils + living ones caught → which is true | a fish off Africa | PP-31 on an animal, with "except Africa" |
| 45 | place near lacks food → extinct | a mountain rabbit | PP-33 with the move branch failing |
| 46 | two kinds, one change → two verdicts | a marsh fish and a bird | NEW |
| 47 | kind changes by learning → the reason | a damp-ground toad | L04-q7 (the bird's beak, yes / no) |
| 48 | kind lives on far south → the reason | a grass-eating antelope | L04-q8 (cool-forest deer, a claim about choosing) |
| 49 | one pond's frogs → the whole kind | Georgia ponds | NEW |
| 50 | fresh description → "adapted" | the kangaroo rat | L04-q11 (arctic fox) |
| 51 | a real past change → the move branch | the caribou | L04's musk ox (the lesson's own case; here a different animal and state) |
v2 — the reviews applied (2 October 2026)
Skill: course-build → write-mcqs → write-explanation @ e23b67f
- The bank is now 51 items = 48 MCQ + 3 typed (easy 17 · medium 20 · hard 14; MCQ keys A 12 · B 15 · C 12 · D 9). "extinct" is TYPED in the hard tier on the coordinator's ruling and leaves
RECALL_BY_MCQ; L03-q11 and PR-14 still recall it by MCQ. - Type 16 (hard, LIF4-051, typed) — the coined word produced from a fresh description, no cue word. Exemplar (PP-44): A huge sea animal called Steller's sea cow once swam off Alaska. The last one died more than two hundred years ago, and no living one is left anywhere on Earth. Type the one word that says what this kind is. — accept: extinct, extint, extinkt, exstinct, extinced, extincted, "extinct.", it is extinct, is extinct, an extinct kind, extinct kind, gone forever, died out. Wrong-answer lines for rare ("A rare kind still has a few living ones…"), gone ("Gone is close. When every one of a kind has died … we say the kind is extinct."), dead. Hard because: the word is produced, not picked (the near-miss grader handles one or two letters off). Nearest lesson-side instance: L03-q11, the recall MCQ (four sisters) — here typed. ⟂ draw constraint: PP-44 is drawn LAST in any test that also draws a type-9 or type-10 item (their options print "extinct").
- PP-28 (type 9, the giant ground sloth) is removed; type 9 now holds 5 items (mastodon, condor, beetle, four described kinds, heath hen). PP-29 "Which of these kinds is extinct?" is retagged easy (a one-step read of the definition) and sits at the end of the easy block as PP-17; every later item's number shifts by one until PP-28's slot, then back (the full list is the bank file's order).
- Type 7 (the drawn cliffs, now PP-24 / PP-25): the stem is "Here is a cliff. What was this place like first, and what was it like later?" — the drawing carries the layers (the figure review's cover test);
cliff_wordsis no longer imported by the bank. - Type 4: PP-12 re-asked as "warm all year" (a fern print / a palm leaf / a maple leaf / a sea shell), PP-13's options a sea shell / a palm leaf / a fern print / a sea star — no key is the odd kind out.
- Type 10: PP-30 (redwood) and PP-43 (the Africa fish) carry "It is rare." as an honest wrong, with the stems giving the count that makes it wrong; PP-14's stem no longer states the definition.
- Accept lists: type 8 (water) adds pond / lake / river / stream forms with articles; type 11 (fossils) adds teeth / skull forms.
- One stated clause on PP-22 (palms cannot stay alive where it is ever cold), PP-23 (a shark can stay alive only in salt water), PP-45 (the rabbit eats the mountain's plants); PP-16 says people have searched the forest every year since 1950.
- PP-49 source: author's observation (no literature source), the lesson lines named.
check_key_tells.py→ KEY TELLS: 0 of 111 MCQs flagged. Blind bundle v2:blind/2026-10-02-v2/(no run of four key letters in any group).
v3 — polish (2 October 2026)
Skill: course-build → write-mcqs @ e23b67f
One stem changed. Type 10's PP-43 (the fish off Africa) now says "many thousands of living ones swim today off the coast of Africa", as PP-30 says it of the redwoods; Reader C read "thousands" beside the option "It is rare." as a hesitation after PP-15 had just made five hundred condors rare. The why says "Many thousands" too. Key and letter unchanged.
Draw constraints on the BUILT bank (v2 numbering, which v3 keeps). The list under "Draw constraints" above is the v1 list, written before PP-29 moved to PP-17 and PP-28 was replaced; this list supersedes it. The test builder reads THIS list.
- PP-10 ⟂ PP-13: PP-10's stem states "a fern can stay alive only where it is damp and shady"; PP-13 keys the fern print for "damp and shady" (Reader C).
- PP-22 ⟂ PP-12 and PP-26 ⟂ PP-12: PP-22's stem states palms cannot stay alive where it is ever cold, PP-26's that big tropical leaves come from plants that need warm all year; PP-12 keys the palm leaf for "warm all year" (Reader C).
- PP-14 ⟂ PP-40: the mastodon (extinct, a ten-thousand-years case) beside the dire wolf (typed "fossils") shows the pair's shape (v1's PP-14 ⟂ PP-41).
- PP-24 ⟂ PP-25: the two drawn cliffs; one per test (v1's PP-22 ⟂ PP-23).
- PP-32 / PP-37 ⟂ PP-45: the trout's and the butterfly's move branch beside the rabbit, whose move branch fails (v1's PP-33 / PP-38 ⟂ PP-45).
- PP-41 ⟂ PP-15: the Labrador duck's distractor "Rare and extinct mean exactly the same thing" is PP-15's lesson (v1's PP-42 ⟂ PP-15).
- PP-44 drawn LAST in any test that also draws a type-9 or type-10 item (their options print "extinct"), as the v2 section says.
- Withdrawn: v1's PP-9 / PP-11 ⟂ PP-12. PP-12 was re-asked in v2 as "warm all year" (key: a palm leaf), so no bank item now keys "a sea shell", and the clam and coral stems give nothing away.
Names in the bank's claims: Travis makes three (PP-31, PP-41, PP-47), Valeria two (PP-28, PP-42), Kayla none. Every bank claim states the verdict in its stem and asks for the reason, so a name there predicts no key. In the quizzes (v3) Travis is right in 2 of 5 claims (L01-q7, L03-q8), Kayla in 1 of 5 (L02-q10), Valeria in 1 of 2 (L04-q10), and each lesson carries one Yes-keyed claim.