Activity 01
Bar Model Building: Ratio Strips
Cut paper strips into ratio lengths, like 2 units red and 3 blue for 2:3. Pairs create equivalent strips by doubling to 4:6, then halve back. They verify using cross-multiplication and record findings.
What defines two ratios as being in proportion to one another?
Facilitation TipDuring Bar Model Building, insist every pair records the scale factor they used on a sticky note so the class can compare strategies later.
What to look forPresent students with pairs of ratios, such as 3:4 and 6:8. Ask them to write 'Yes' if they are in proportion and 'No' if they are not, showing their working. Then, provide a proportion with a missing value, like 5:10 = ?:20, and ask them to calculate the missing number.