Yesterday, Year 6 made pumping heart models to demonstrate the circulatory system. We use bottles (the atrium, the ventricle and the body), straws (the valves), water and food colouring (the blood) and blu-tack to show that blood can only flow in one direction around the body. When we squeezed the valves between the atrium and the ventricle, the blood flowed from the ventricle into the body - just like a real heart!