While children in this age group are physically able to turn the steering wheel and reach the gas pedal of these motorized vehicles, they lack the coordination, the reflexes and the judgment to avoid crashes. For that reason youngsters should not be allowed to drive them.

In addition, these vehicles achieve high speeds but provide no protective covering. Therefore, when a crash does occur, there is a high risk of serious injury. Minibikes (two-wheeled vehicles that resemble small motorcycles) have a crash rate 400 percent higher than that of bicycles, with most injuries occurring from falls or collisions. There are more than 30,000 crashes per year on trail bikes, with about one third of them occurring in youngsters under the age of 14.

ATVs have received considerable attention in recent years - much of it negative because of their high crash rates. These off-road vehicles can achieve speeds as high as 30 miles per hour to 50 miles per hour, and they enjoyed a surge in popularity in the 1980s. But the three-wheel models in particular are prone to overturning on hills and slopes. Many children have died, often after suffering serious head injuries. Head injuries also are responsible for deaths on snowmobiles, which can achieve high rates of speed and are prone to rollovers. Tractors, riding mowers, and personal watercraft also tend to roll over, causing serious injuries. None of these vehicles are appropriate for children to drive.