My son used this to do his 3rd grade science project and won 2nd place! We had a blast doing it. I would recommend finding a large straight area to do this. My one problem with it was that it was difficult initially for my son to stomp on to release the rocket.
Great toy. It was easy to set up, fill up and release. It was great fun for the kids. They enjoyed watching the car race up the driveway, plus it was great exercise for them to get the car and do it all over again.