Roller coaster?

Question

For a school project, I have to make a coaster that has three requirements

1. It must go back to the top by itself, meaning what can i use to make my roller coaster or marble get back to the top of the hill all by itself. ex. conveyor belt (don't have one)

2. It must work

3. It can be a roller coaster or log flume

p.s. I already tried a chain and coilgun (dont work) any ideas on what material to use and what to use to get it back up.

Answer 1

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