Children at St Andrew’s Primary School, in Keighley, found the formula for fun.

Mad Science, an organisation that delivers scientific-based activities in schools, staged a special assembly.

The whole of Key Stage Two — more than 200 children — attended the event, led by Julia Hatton.

The youngsters took part in experiments illustrating condensation, sublimation and the effects of changes in air pressure using dry ice, foam and “Eggbert” — an egg that couldn’t fit into its house until a scientific solution was found.

The event marked the launch of a new after-school club which will run at St Andrew’s for six weeks.

Sessions, which will be led by Mad Science, have been funded with a grant obtained through the Extended Schools initiative.