Standard units of measurement are usually introduced in Year 2. Children should already be familiar with the metre and once they can count fluently to 100 and beyond the centimetre can also be introduced. Quite a tricky word to spell too! At first it is a good idea to practice drawing lines less than/about the same as/more than a centimetre in length. This should help with grasping the approximate size of a centimetre. Unfortunately many adults still use the term 'inch' when talking about small measures. Watch out when your child starts to use a ruler to measure. Most rulers have a space away from the edge to start measuring from, but they are not always marked with a zero. Watch out, also, for the child who starts at the edge Note that all measurements are approximate on this page as printers do print at slightly different sizes, depending on the settings used, paper size etc. Introducing the centimetre