Students play the role of engineers as they test, design and build Mentos fountains - a dramatic example of how potential energy can be converted to kinetic energy. They are challenged to work together as a class to optimize the design of the basic soda/candy geyser made by the teacher. To do this, three research teams each investigate how different variables affect fountain height. Then they combine their results to design the highest fountain to compete head-to-head with the teacher's geyser design. The video shows examples of Mentos geysers using different liquids going off at the same time in front of a garage door. Through this activity, students gain experience testing, evaluating and optimizing a design, as well as collaborating with other engineers or research groups. As part of the assessment, teachers evaluate how effective the teamwork was.