Code: AC9M4N03 (partial). Goal: connect a quarter and three quarters of one equal whole to hundredths and decimals. Prepare: four-part same-sized strips, 10×10 grid, 0–1 line.
- Invite · 2 min. Fold one strip into four equal sections. Ask how many of the hundred small cells in a same-sized whole would match one quarter.
- Model · 5 min. Partition 100 equal cells into four groups of 25. Shade one:
1/4 = 25/100 = 0.25. Shade three groups on a new matching whole:3/4 = 75/100 = 0.75; place both at quarter and three-quarter points on a 0–1 line. - Guided · 6 min. Build
2/4 = 50/100 = 1/2 = 0.50; contrast one quarter and half using aligned equal wholes. Explain why 25 cells are one quarter of this grid. - Choice · 6 min. Choose D17-A/B/C. Use 25-cell groups, quarter folds or a learner-directed tactile grid.
- Exit · 4 min. Compare
1/4 = 0.25with0.2 = 0.20: the quarter is greater by five hundredths, with the same whole. - Note · 2 min. If a child maps one quarter to
0.4, count four groups of 25 or fold the same whole again; do not rely on a memorised decimal alone.
Access/home/extension: A 100-cell grid can be described as four equal 25-cell blocks, not visually scanned. Extension: explain 3/4 as one whole minus one quarter.