When buying an ATV for the kids, one size does not fit all. At Carlsbad Small Engine we follow the manufacturer recommended age requirements. It is regulated by the state and the feds. It's also the right thing to do. The size fit of the ATV is important so they can handle the controls properly. Also the power and top speed is impacted by the age. Consider maturity as well. Don't put your kid on something they shouldn't be riding, it's not safe. If you need help with training we provide links on the web site to all sorts of training to make your riding experience better and safer. Good riding!