Topics · Shapes & Measurement
Measuring things
Pick the right unit — mm, cm, m, km, g, kg, mL, L — and convert bigger units into smaller ones.
Measuring in the wrong unit makes silly answers.
More ways into this idea
- Make it a gameMeasure UpReach the target exactly — big pieces, small pieces, your choice
- Test yourselfA fresh mixed set, whenever you likeExplanations after every question. Nothing is recorded.
Common sticking points
- The big one is expecting a smaller unit to give a smaller number — turning 3 kg into 0.003 g. It is the other way round: a gram is small, so it takes a thousand of them to make one kilogram.
- Another is comparing measurements by their numbers without reading the units — deciding 150 cm beats 1.4 m. Put both into the same unit first and the comparison becomes obvious.
- A third is choosing a unit that is the right kind but wildly the wrong size. Checking an answer against something familiar — a fingernail is about 1 cm, a doorway about 2 m — catches it every time.
Try this together
Pick something in the room and guess its length in centimetres before measuring. Then ask the harder question: what would the same thing be in millimetres, and is that number bigger or smaller? Do it once with a jug of water in millilitres and litres too — the pattern is the same, which is the whole point of the metric system.
1–5 minutes, no materials to buy, nothing to hand in.
Ontario curriculum details
- E2.1Estimate and measure with metric units
- E2.2Convert larger metric units to smaller ones
Plain-language summaries. See the full curriculum for every expectation and the official source.