Charlie's delightful machine Play with our interactive machine and see if you can work out how to switch each light on. Is there a way to turn on all four lights at once? Age 11 to 16 Exploring and noticing Working systematically Conjecturing and generalising Visualising and representing Reasoning, convincing and proving Being curious Being resourceful Being resilient Being collaborative Problem Problem Play with our interactive machine and see if you can work out how to switch each light on. Is there a way to turn on all four lights at once?