Children can see chain reactions in action, slow at the start then accelerating until the circuit concludes. Children will learn how speeds vary depending on the weight of the object and the distances between them. Great fun while children learn introductory physics concepts without realising! For ages 7 and up. WARNING: CHOKING HAZARD – Small Parts. Not for children under 3yrs. WARNING: CHOKING HAZARD – Toy contains a small ball. Not for children under 3 yrs.