Tain Roberts, James Miller and Braydon Gill (all 12), of Alexandra Primary School, recharge their tiny robots. Photos by Lynda van Kempen. : Pupils say science festival bang on

Lewis Adamson (left, 11) and Harry Wing (11) of Cromwell College, taste the sugar levels in various drinks. : Pupils say science festival bang on

Meleah Manderson (12), of Roxburgh Area School, with a buzz-bot robot. : Pupils say science festival bang on

Cromwell College pupil Tom Coudret (11) takes a closer look at some lighting effects. : Pupils say science festival bang on

Testing pH levels of liquids are Clyde Jeffery (left, 11), and Reuben Hodgkinson-Harris (12), of Roxburgh Area School. : Pupils say science festival bang on

Sophie Robertson (11), of Cromwell College, inhales the aroma at the food science workshop. : Pupils say science festival bang on

Dave Warren, outreach co-ordinator at Otago University’s chemistry department, "primes" the volcano, a demonstration during a two-day mini science festival held in Alexandra this week. : Pupils say science festival bang on

Dave Warren, outreach co-ordinator at Otago University’s chemistry department, "primes" the volcano, a demonstration during a two-day mini science festival held in Alexandra this week. : Pupils say science festival bang on

Mr Warren removes the "core" of the volcano before it erupts. : Pupils say science festival bang on

A "volcano" full of 1500 ping-pong balls erupts during the science workshop. : Pupils say science festival bang on

Pupils race to clean up the broken balls. : Pupils say science festival bang on