Topics · Numbers & Calculations
Big numbers
Read, build and compare numbers all the way to 100 000.
Big numbers are everywhere: populations, distances, scores.
More ways into this idea
- Play with itPlace Value MachinePile blocks into columns, trade tens, pull the ×10 lever
- Make it a gameAbout How Much?Throw a net over the number line before you calculate
- Make it a gameNumber BuilderBuild big numbers from place-value pieces — and trade them
- Test yourselfA fresh mixed set, whenever you likeExplanations after every question. Nothing is recorded.
Common sticking points
- A common sticking point is reading a digit as its face value: the 4 in 42 315 isn't 4 — its place makes it 40 000.
- Another is dropping zero places. In 40 205 the zeros hold their places open — skip one and every higher digit loses ten times its value.
Try this together
Write the digits 4, 2, 7, 0, 5 on scraps of paper and arrange them as 42 705. Ask: what happens to the 4's value if we slide it one place right? One place left? (It divides or multiplies by ten every move.)
1–5 minutes, no materials to buy, nothing to hand in.
Ontario curriculum details
- B1.1Read and build whole numbers up to 100 000
- B1.2Compare and order whole numbers up to 100 000
Plain-language summaries. See the full curriculum for every expectation and the official source.