Mathematics
Beginner
50 mins
Teacher/Student led
Learning Goals
Learning Outcomes
Lesson Files
+65 XP
Teacher-led from the board. Pupils do not need a device, but can follow on one.
What you need:
IWB/Projector/Large Screen

Rounding to the Nearest 100

Learn to round numbers to the nearest 100 by identifying which hundred they sit closest to, using the tens digit to decide whether to round up or down.

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    1 - Getting Started ~4 mins

    Look at this number: 350. On our line it sits right between 300 and 400. So which hundred is it nearer to, 300 or 400? Hands up if you are sure, and be ready to tell us how you decided.

    👇 Mark your steps as done as you complete them.

    +5 XP

    2 - Watch and Notice ~10 mins

    The interactive shows each number sitting on a number line between two hundreds. Watch where it lands, and decide which hundred it is nearer. Keep an eye on the tens digit: if it is 5 or more, the number is halfway or past it, so we round up to the higher hundred.

    Check: which hundred is 320 nearer?

    320 is nearer 300. It has not reached the halfway mark, 350. Its tens digit is 2, which is less than 5, so it rounds down to 300.

    Check: which hundred is 480 nearer?

    480 is nearer 500. It is past the halfway mark, 450. Its tens digit is 8, which is 5 or more, so it rounds up to 500.

    Check: which hundred is 650 nearer?

    650 sits exactly on the halfway mark between 600 and 700, so it is not nearer to either one. The rule for a halfway number is to round up, so 650 rounds to 700. Its tens digit, 5, says the same.

    Check: which hundred is 3,470 nearer?

    3,470 is nearer 3,500. It is past the halfway mark, 3,450. Its tens digit is 7, which is 5 or more, so it rounds up to 3,500.

    👇 Mark your steps as done as you complete them.

    +10 XP

    3 - Try It Together ~11 mins

    Today we work through these together on the line, in this order: 240, then 760, then 2,650, then 4,970. Each one adds a wrinkle. For each number we find the two hundreds it sits between, drag the marker to it, then read off the nearer hundred. Watch the last one carefully.

    Round to the nearest 100

    +15 XP

    4 - Round Them in Your Copy ~3 mins

    COPYBOOK MOMENT

    In your maths copy, round each of these four numbers to the nearest 100. Beside each one, first write the two hundreds it sits between, then circle the one it rounds to.

    • 280
    • 740
    • 2,650
    • 4,970

    Writing the two hundreds first stops you guessing.

    +10 XP

    5 - Class Challenge ~8 mins

    Today's challenge numbers, in order: 280, then 740, then 2,650, then 4,970. Each round pushes a little further. Find the two hundreds each sits between, place the marker, and press Check to confirm the nearer hundred.

    Round to the nearest 100

    +15 XP
    Pupil practice
    Module 1 · Place Value: Whole Numbers to 9,999 and Rounding Number
    Lesson 10 · Rounding to the Nearest 100
    Download Activity Book page (PDF)
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