My Year 3 children really enjoy the science topic "light and shadows". It can be linked to many interesting investigations. My children love making shadow puppets and quickly learn that if a light source is blocked then a shadow is formed. Taking this concept further the children can investigate how shadows can be used to tell what time it is.
This task needs to take place outside on a sunny day. On the hour, take the children into the playground. One child stands alone in an open space (you don't want any other objects to cast a shadow into this area) and another child draws around the child's feet with chalk (call the feet markings the "person marker"). Every hour the same child returns to the person marker. A shadow will be cast onto the playground. Another child draws around the head part of the shadow. In this chalked shape write the time, for example 9 am.
Continue this throughout the day to make your human sun clock. Children can return to stand on the person marker to see where their shadow points. If it points directly to a number it is that hour, if it is in the middle it is half past and near to a number is quarter past or quarter to.
Kay Coverdale, Wheatlands School, Redcar, Cleveland