By year 6 children will be very familiar with the metric system, but here is a worksheet which should test their knowledge and ability to convert from a larger metric unit to a smaller one. It involves converting metres to centimetres, centimetres to millimetres, kilograms to grams and litres to millilitres.What makes it more tricky is that all the larger measurements use decimal fractions as well as whole units. This of course, needs careful multiplication by 10, 100 or 1000 and ‘adding a nought’ just won’t work!