Estimate the number the arrow is pointing to, then calculate the correct answer when you are told your error. A great game to help develop an understanding of place value, reading scales and to practise mental addition and subtraction. There are lots of levels to play; inc. 0 to 10, 0 to 100, 0 to 1000, and levels involving negative numbers and decimals.

This is a new version that will work on tablets or any device.