Codes: AC9M4N03, AC9M4N01 (partial). Goal: test equivalent representations and compare across related fractions/decimals with fixed wholes. Prepare: candidate cards 3/4, 0.75, 1/5, 0.20, 1/2, 0.50, same-sized strips.
- Invite · 2 min. Ask whether a larger denominator automatically makes a larger amount. Keep the unit whole fixed while gathering claims.
- Model · 5 min. Match
3/4 = 75/100 = 0.75and1/5 = 20/100 = 0.20. On the same 0–1 line, their positions differ; the denominator alone does not order them. Link each to its same-whole model. - Guided · 6 min. Match
1/2, 5/10, 0.50at one point and order0.25, 0.50, 0.75. Ask why one full-size strip cannot be compared by raw cell count with a differently sized strip. - Choice · 6 min. Select D19-A/B/C. Learner creates or rejects a match with an exact model/reason and names the whole.
- Exit · 4 min. Are
0.50and0.5different points? No; 50 hundredths = 5 tenths. Ask for a second representation of the same point. - Note · 2 min. Record whether the learner matched by quantity or by digit appearance. If wholes drift, overlay same-size outlines and recheck with a new pair.
Access/home/extension: Tactile strips, line locations and verbal ratio explanations work without colour. Extension: give a counterexample to “more pieces means more shaded amount.”