What if?

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Discuss what times as many means. For example, a kangaroo can jump four times its height means it could jump over four kangaroos lying on the ground head to toe. This means if you were a kangaroo, you could jump over four of you lying head to toe. This could be physically demonstrated by having four students of a similar height lying head to toe along the ground.

Students learn about the jumping distance of several animals and then estimate the lengths of jumps they would make if they were those animals.

Have students measure and record their height, using decimal notation, eg. 1.35m.
Ask students to work out how far they could jump if they were a kangaroo. Allow them to use their own strategies. Some strategies might include:
- measuring out four height lengths
- adding together their height four times and then measuring
- multiplying their height four times and then measuring
- doubling their height and then doubling again.
Ask students to calculate how far they could jump if they could jump 20 times their height (grasshopper), 30 times their height (frog) or 200 times their height (flea).
Where possible, have students mark out their kangaroo, frog, grasshopper or flea jumps around the school.
Students work backwards to predict how many times their own height they could jump.
After predicting, students complete a run and jump finding the difference between their actual jump and their prediction.

Record heights in different formats, eg. whole metres and centimetres, centimetres, metres.
Use a table to record calculations.

Geometric measure