I bought this as a gift for my nephew who loves science and loves to experiment and build things. It comes in a real cool scientific looking box and he loved it! Cool idea!!
I am a high school physics teacher and I could not have been more pleased with this purchase. I also grabbed several extra fuel packages. We tried it out in our hallway after a department meeting and everyone was impressed by the speed of the car. That said, kids might not be as impressed as a bunch of science teachers were. It took 5 minutes to set up for a 10 second ride, after which we all stood around and discussed the chemistry and physics involved. Will your 8-year old do this? Probably not. Parents - expect to be a full participant.
I purchased this product for a friend's son's birthday party and he loved it. I know the age on the box says 8+ but the party was for a child turning 5. His father will help him of course but both of them (the father and son) were excited to "build a rocket."