My dad used to explain astronomy to me using salt pots and oranges. The orange generally represented the sun, whilst the salt pots, ketchup bottles and whatever else was on the kitchen table stood in for planets and comets. He would then make them all ‘orbit’ each other, enlisting my help when he ran out of hands and demonstrating why the moon seemed to change size each night, or how a solar eclipse worked. Despite the side effect of my food often going cold as I turned forks into astronauts, I remember much more about distances between planets than I do about the floodplains I was forced to study in class. I am sure that this is mainly due to the teaching style – getting directly involved with a demonstration and seeing how my actions changed the situation was much more engaging than making notes from a PowerPoint presentation.