to wear a helmet when riding a bike. I insist that my 10 yr old wear one though. It is a simple thing that brings a great amount of benefit for a small price in money and impact on the activity. An ER Dr. friend of mine has told of too many horror stories of the injuries sustained from not wearing a bike helmet to have such a small thing be simply an option for my kids. Wearing a bike helmet is a tiny inconvenience if that. We also all wear seat belts at all times when in the car.