Massive Erupting Volcano STEM Experiment Kit. Thames and Kosmos. This Massive Erupting Volcano STEM Experiment Kit lets you simulate your very own earth-shattering 30cm volcano at home! Slide the sturdy cardboard frame together to build a huge volcano replica, using hardening plaster-coated fabric strips to make it looks real! Then, its up to you to bring your volcano to life. Paint it and decorate it with the included dinosaur cut-outs and pre-historic trees!