Watch That Giant Geyser Explode With Hands-On Science Fun: Ready to wow your science students, homeschoolers, or camp kids? Our Geyser Tube event pack comes with 10 improved tubes and packs of Mentos candy so all you need to prepare are the 2-liter bottles of soda. Add the candies and see how high the resulting geyser blows-many reach upwards of 30 feet in the air! Our special trigger-mechanism features help ensure ideal launches without mishaps or getting accidentally soaked. Kids squeal with excitement when they see the gaseous chemical reactions in action. Sturdy tubes can be reused again and again. Our safe & durable STEM toys are crafted to last and be passed around for years of educational opportunities. Steve Spangler Science experiments-taking hands-on learning to awesome levels while teaching children about fantastic STEM concepts.