Groups can disagree because methods or materials differ. Check methods before combining results. A possible reason is not a proven cause; use it to ask a clearer question. Safety: Use stable floor supports and the light pencil only. Stop: End after the two practical tests and supplied-case comparison. Do not add loads or test furniture.

Materials: Two paper sheets, pencil and ruler; Two equal-height stable books and one wooden pencil; Adult partner 1. Agree on a bridge test: books 10 cm apart on the floor, one flat sheet overlapping both supports, one wooden pencil placed in its centre for a slow count of five. Draw a table Person | Gap | Paper | Result | Method note. 2. The learner and adult each set up and perform the test separately using the same materials. Record holds or touches floor and any actual method difference. Do not alter a result to make the rows agree. 3. Compare the two rows. State what agrees, what differs and whether each followed the agreed method. Identical outcomes are valid; you do not need to produce disagreement. 4. Analyse these illustrative group records, not real observations: Red used a 10 cm gap and one sheet; it touched the floor. Blue used a 5 cm gap and one sheet; it held. Green used a 10 cm gap and two stacked sheets; it held. Write why these cannot show that one group’s paper is better. 5. Give a limited conclusion about your actual pair of tests. Then write a new question, such as Would changing only the gap change the result? State what would stay the same. Done: Complete two real rows, compare the supplied three-group case and propose one fair follow-up question. Proof: Keep both tables and the new question. Note adult help and whether separate setups occurred. Stop: End after the two practical tests and supplied-case comparison. Do not add loads or test furniture.