Creating your own 12 foot high fountain of fizz doesn't need to be hard at all. This Geyser Tube makes it a snap. Just grab a bottle of Diet Coke, screw on the geyser tube, load it up with the included Mentos, and pull the string. Whoosh! A real crowd pleaser. Get some more Mentos to use it over and over. Oh yeah, it also teaches about nucleation sites and the spontaneous release of carbon dioxide.