Collison of Vehicles

just had fun making a ramp out of a binder and experimenting with the steepness as one car collided into another car.I did have an idea that the steeper hill would make more force as well as an increase of mass. My experience of riding bikes up steep hills has taught me a lot.I ususally can't keep up with my daughter until we coast down. Then my larger mass gives me an edge.The experiment I designed went like this: I held the truck on a marked spot at the top of the binder then let go for it to hit another car left at the bottom on a marked spot. After they collided I drew a line under the one that got hit. I placed paper under it before the experiment. Then after 3 hits I raised the ramp by putting a pillow under it. I repeated the same experiment and marked the hit car to notice it went further and was hit with more force.I did each type 3 times each.Then I taped on a quarter to the car at the top of the ramp to test how mass might affect a collision. The ramp stayed the same and I did 3 hits with a quarter and 3 hits without. It was clear that the greater the mass the more forceful the collison. Both experiments worked well, and they are simple enough for First graders, so I would not change a thing. However, I did think the cars were a little cheap and my modification would be to use metal match box cars. I think the higher quality wheels would produce better results. It might also be fun to add little people to see how far they fly.