Practise rounding to the nearest 100 worksheets on a number line — kids see the two round numbers, find the midpoint, and write what the number rounds to. Every sheet prints with a matching answer key. Three-digit numbers on a number line between two hundreds — decide which hundred is nearer and round. Free, no signup.
Opens the builder set to to the nearest 100 · 8 number lines per sheet · free, no signup.
Rounding to the nearest 100 works the same way, one place value up: the two neighbouring hundreds sit at the ends of the line and the halfway mark — fifty — is in the middle. 235 is short of 250, so it's closer to 200 and rounds down; 280 is past 250, so it rounds up to 300.
Quick way to teach it: Look at the tens digit: 0–4 rounds down to the lower hundred, 5–9 rounds up to the next. Underlining the hundreds digit and peeking at the tens beside it keeps the decision quick.
Look at the tens digit: 0–4 rounds down to the lower hundred, 5–9 rounds up to the next. Underlining the hundreds digit and peeking at the tens beside it keeps the decision quick. Print a fresh sheet, work a few number lines together each day, and check with the answer key — short, regular practice beats one long session.
This is usually taught in Grade 3 & Grade 4. Rounding to the nearest 100 works the same way, one place value up: the two neighbouring hundreds sit at the ends of the line and the halfway mark — fifty — is in the middle. 235 is short of 250, so it's closer to 200 and rounds down; 280 is past 250, so it rounds up to 300.
Look at the digit one place to the right of where you're rounding. If it's 5, 6, 7, 8 or 9 you round up to the next multiple; if it's 0, 1, 2, 3 or 4 you round down and keep the multiple you have. The number line shows why: the midpoint is exactly halfway, so anything on or past it is closer to the larger number.
A number line turns rounding from a digit trick into something you can see. The two round numbers sit at the ends, the halfway mark sits in the middle, and the number you're rounding is plotted between them — so a child can literally see which end it's nearer to before learning the shortcut. It's the bridge from understanding to fluency.