Learner copy · two fresh independent checksYear 9 Inquiry · T1 W3–4 · Learner checks

Use on Days 15 and 20. These prompts are fresh relative to the lessons, but the public library also exposes their teacher key, so they are not secure exams. A teacher should adapt the invented case if learners may have seen answers. Both cases are entirely invented. Units are arbitrary sensor units; no actual material or room was tested. Calculator, large print, read-aloud, tactile number cards, AAC and exact-word scribe are access choices. Work alone on the first response. State the source for a claim and keep prediction separate from record.

Check A · Day 15 · folded card notice

An invented Folded Card team wrote: “Each added card always halves the sensor value. The improvement proved reliable viewing.” Its one invented tabletop table starts at 96 and lists: zero cards 96, one 48, two 27, three 18. The team gives no calibration, repeated readings or background-light note. Let P(n)=96×2^-n be the conditional exact-half model.

1. Find P(3) using a negative exponent and show why the exponent does not mean a negative sensor value.
2. Compare P(3) to the listed three-card value with a signed record − prediction gap. Identify which source statement this comparison tests.
3. Explain how “the improvement” hides an actor, an action or a particular comparison. Rewrite the final sentence so the team, invented record and a limit are visible. Do not claim reliable viewing in a real place.
4. Give one precise additional measurement or method detail you would request before a stronger claim.

Check B · Day 20 · theatre backdrop paper

An invented theatre group suggests that every extra sheet halves a sensor reading from a baseline of 120. They list three fictional rounds:

The note says “same desk,” but gives no sensor calibration, paper specification, background light or independent observer. No real stage use has happened.

1. For P(n)=120×2^-n, calculate P(3) and compare it to the middle of the three-sheet round values. Show the numerical gap.
2. Explain what is consistent within the three-sheet rounds and what the table cannot show about independent reproducibility or other conditions.
3. Write an investigable question and two operational controls for a supervised retest. State whether your written plan itself proves the retest occurred.
4. Write a short recommendation for the fictional group: decision, source-bound numerical reason, method limit and a next check. Do not approve public use or state a real safety result.