Code: AC9M6N03. Goal: locate 1/4, 1/3, 1/2 in order on one 0–1 line. Prepare: fraction line and equal-whole bars or 12 equal tactile strips.
- Launch · 2 min. Ask why “one half is bigger than one third” needs the same-size whole.
- Model · 5 min. Mark 0 and 1, then 12 equal spaces. Place
1/4at gap 3,1/3at gap 4,1/2at gap 6. Explain3/12 < 4/12 < 6/12; point to the same endpoint 1 for all. - Guided · 6 min. Learners use bars split into 2, 3, 4 or 12 equal parts and map
1/2=6/12,1/3=4/12. Ask whether gap 6 on a different 6-gap 0–1 line has the same value as gap 6 on this 12-gap line. No:6/6=1, while6/12=1/2; the scale matters. - Choice · 6 min. D16-A/B/C: line, recipe-share cards or a musical-cycle fraction route; each uses one whole and justifies order.
- Exit · 4 min. On the same whole, order
1/2,1/4,1/3:1/4 < 1/3 < 1/2. Explain by twelfths or equal bars, not denominator size alone. - Note · 2 min. Record whether endpoints and equal spacing were checked. If not, restore a shared whole before rechecking.
Home/extension: Fold a paper strip into 2 then 4 equal parts, or draw 12 gaps; no food or instrument needed. Extension: explain why differently sized physical wholes make direct piece comparisons unsafe.