A homemade roller coaster project teaches many scientific principles. Some of the most important are kinetic energy, which is a measure of the energy an object has due to motion, which is why the first hill is always the highest point of a coaster. Gravitational potential energy is a measure of the weight of an object multiplied times its height. Students will have to take these principles into consideration in order to build a successful homemade roller coaster.
For the paper roller coaster, the coaster car will be a simple marble. All students or group of students should have a marble that is the same size or weight. Instruct them to use paper, glue, tape and scissors to make a roller coaster. It must be a complete circuit like a real coaster and it can not move or shake while the marble is in motion. If it falls apart or the marble goes off the track or doesn't get all the way till the end without help, they must revise the coaster plan. Have them keep a journal of all the steps and plans they did in order to get to the final project. For more advanced students, requirements like a loop or camel back (two hills in a row) can be added to the requirements.
Students must use either corrugated cardboard or foam board in order to make a roller coaster, with a tennis ball serving as the coaster car. Hot glue will serve as the adhering material, so make sure the students are old enough to safely use a hot glue gun and a box knife to cut the boards. The coaster must have at least three hills, and the students with the highest combined height of those three hills will be declared the winner of the contest.
For this coaster projects, students must determine on their own which materials will be used to construct their coaster. They must also keep a journal of their plans and all changes made to the plans and materials as a result of testing. Keep the rules simple so that they do as much of the design as possible for themselves. The only stipulations should be that it is attached to a base but is otherwise freestanding, must be portable, no weight limit, and can't be higher than 1 meter. A golf ball should serve as the coaster car. Assign this project so that the students have several days or even weeks to fully test several versions of the coaster until they get one that keeps the golf ball on the track successfully.