In this activity, learners create a colorful foam fountain by adding yeast to a chemical reaction. This activity introduces chemical reactions to young learners and teaches the concept of catalysts. Activity includes step-by-step instructions, questions to engage learners, and an explanation of the science behind the activity. This activity uses low cost materials and can be done at home. Safety notice: This activity uses hydrogen peroxide-do not use solutions of hydrogen peroxide greater than 6% concentration.