Math · Stage 4
Convert between units of length, mass, capacity and time; solve measure problems
Every big unit is made of equal small ones — step down × (10, 100, 1000, 60, 24), step up ÷ the same — then use it to solve real measure problems.
✦ Math📘 Stage 4 · S4⏱ ~12 min🧒 Ages 8–9★ Free to start
I can convert between units of length, mass, capacity and time; solve measure problems.
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Kavi's Measuring Day 📏
Kavi is busy: measuring a 2 km trail, weighing a 3 kg melon, filling a 1 l bottle, and timing a 2 hour film. "I can say each one the small way too," hoots Kavi. "2 km is 2000 m, 3 kg is 3000 g, 1 l is 1000 ml, and 2 hours is 120 minutes ⏱️! Every big unit is just lots of equal little ones — so I can convert, compare and solve."
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What your child will learn
1The length ladder: mm · cm · m · km
2A ruler counts in tens of mmA ruler is a numberline! Each hop of 10 mm is exactly 1 cm. Start at 0 and tap Hop +10: 10, 20, 30, 40, 50.
3The thousand club — and the clock
4Length, mass, capacity or time?
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A peek inside
A trail is 3 km long. How many metres is that?
km → m is the small way → × 1000 → 3 × 1000
Try this at home: Length: 1 cm = __ mm · 1 m = __ cm · 1 km = __ m
Ready to play and learn?
Start the free interactive lesson, or print the handout for screen-free play.
Part of Math · Stage 4 · S4 on KAVI Academy — a secular, whole-child learning platform for ages 5–12.