Ten pupils stand at the front holding number cards 1 to 10, making a human number line. Where does 0 belong, and why at that end?

Now the children in the line turn their cards around, all except 5 and 10. Can we still work out every hidden number? How do we know?

Here is a number line from 0 to 10. Every number has its own place, and each step along the line is one more.

Only 0, 5 and 10 have their names on the line. 5 is our landmark. It sits in the middle, and it helps us find the numbers near it.

Find 3. Start at 0 and count three steps: 1, 2, 3.

Find 7. Start at our landmark 5 and count two steps on: 6, 7.

One more than 5. Start at 5 and take one step on. We land on 6.

One less than 9. Start at 9 and take one step back. We land on 8.

Now we find numbers on a line where only 0, 5 and 10 have names. One pupil drags the marker, and everyone else counts the steps out loud.

We will find 4, then 8, then 1, then 9. Before the marker moves, we say where to start: at 0, at 5 or at 10?

Only 0, 5 and 10 have names on this line. One pupil places each number on the board, and everyone else says the number with the class. Place 2, then 6, then one more than 7, then one less than 10. For the last two, say the number first, then the board pupil drags.

Which landmark helps you find each one fastest: 0, 5 or 10?