In this activity students have the chance to study the conservation of Mechanical Energy using a roller-coaster made by the group. Students will have to measure the speed of the object that moves on the roller coaster at a certain height of the path and determine the kinetic and potential energy of the object. Students must conclude if there is or is not a conservation of Mechanical Energy in the roller -coaster the students have made. They learn about the possibilities and limitations of roller coasters within the context of energy conservation, frictional losses and other physical principles.