Jumps of ten

1. This is a number line. It runs from 0 to 100. The tall marks are the tens. The marker is sitting on 0.
2. One jump of ten. Watch the marker move. It went from 0 to 10 in one go. That is a jump of ten.
3. Another one, the same size. From 10 to 20 now. Look at how far it travelled. It is exactly the same distance as the first jump.
4. Keep jumping. Three more jumps of ten. Every one covers the same ground. Count them as they go: 30, 40, 50.
5. Your turn. Get to 40. The marker is back on 0. Press a jump to move it. Get to 40, and watch how many jumps it takes you.
6. Here is 40 again. Four jumps of ten got us here. Now for a different size of jump.
7. A jump of one is small. Three jumps of one, from 40 to 43. Look how little the marker moved. A jump of ten goes ten times as far.
8. Four more ones makes 47. From 43 to 47. So 47 is four jumps of ten and seven jumps of one. That is what the 4 and the 7 in 47 are telling you.
9. Your turn. Get to 47. Back to 0. Get the marker to 47. Do the tens first and the ones after, and it will take you eleven jumps.
10. Last check. The marker is on 30. Think about the size of a jump of ten. You are on 30 and you jump ten. Where do you land? 40 · 31. Yes. A jump of ten takes you from 30 to 40 in one go.

A jump of ten is the same size wherever you make it. Four tens and seven ones is 47. And jumping in tens is much quicker than counting in ones.