This is an exciting culminating project I use after completing our unit on Forces and Motion. With this project, students research the design of a roller coaster, design their own roller coaster, and make it come to life in class! For the construction, all you need is gray pipe insulation - cut in half, duct tape, and marbles. A rubric is included to help guide students so they'll know what is expected of them. There are guided steps to ensure students are including (and labeling) the forces and laws they've learned about.
This is one of the activities that students come to the eighth grade SO excited about. It usually takes three to five days depending on the type of class you have. You can modify the project to have students just design or just build or complete all three parts. There is a final product component, as well, in which students explain their design and the forces involved.
I use this project-based learning task as a formative assessment.
Please contact me with questions!