What does one litre look like? You need to bombard your Year 2 – 6 students with this constantly so they develop an effective visual representation in all shapes and forms. Here are 2 new litre photographs – milk and juice. Ask everyone to collect their own litre containers and bring them in to school. Fill them with water outside in the playground and then watch as students pour their litre of water into a wide variety of other shapes. Ask them to estimate where the level may go up to, think about what a half or quarter of a litre might look like, 100 mL, 200 mL and so on. Give an award at assembly to students who can estimate a litre to within a 10% accuracy level.