This multi-activity kit lets students experience the power of stoichiometry. After using stoichiometry to predict the mass or volume of reaction products, students both decompose sodium bicarbonate and react sodium bicarbonate with hydrochloric acid. They use their observations and collected data to calculate percent yield and percent error. Activities require about 90 min to complete; can be done in separate class periods. Kit materials equip 1 class of 30 students working in groups of 3.