In the back seat, children are away from airbags, which eliminates the injury risk from front airbags deployed during a collision. In the back seat, they also are farther from hard surfaces such as the windshield and dashboard that can result in serious head injuries and death. Finally, children properly restrained in the backseat are protected from ejection from the vehicle in the event of a crash.
All children under 12 years of age should ride in the back seat!