Derived facts
Multiplying by 10 and 100
Children need a strong grasp on this concept in order to work out derived facts. See multiplying and dividing by 10 and 100 for more information.
This needs to be taught during place value input when you explain how the numbers get 10x bigger when you move left, and 10x smaller when you move right. Children need to understand that when you move left twice, you are doing 10 x 10 which is the same as multiplying by 100. Similarly, if you move right 2 columns, you are dividing by 10 and then dividing by 10 again, which is the same as dividing by 100.
A great way of teaching the basic concept is using chairs. (photo coming soon!)
These sliding whiteboards are fantastic once children understand the basic concept.
I used place value counters a lot to teach this concept and it was hugely successful.
This also works with division, which is what Gareth Metcalfe showed us at some training:
Derived facts tests can also be found here