How far can a model car run on hydrogen? You start by connecting up the leads and seeing the hydrogen come bubbling up out of water – and oxygen too.
And it was a day when you could make paper from natural materials, paint a 3D-printed butterfly or steer a Mars rover.
You could learn to use an astronomical telescope, or make a cloud chamber and see particles from outer space.
You could operate a robot arm to remove marine litter, or find out about seashells and the creatures that live in them. Or you could learn how to turn old fabrics into new in the upcycling workshop.
It was a day when the whole family could be involved in a range of fascinating activities.