Geyser Tube with Caps
Learn to create an enormous geysesr by combining Mentos with soda.   The eruption is amazing - up to 25' high - and so is the learning if you consider the science just beneath the surface.   Interchangeable caps fit on the Geyser Tube to allow various types of sprays:  a single spray; a long, rectangular spray; a cross and a 3-hole spray.