teaching them to ride, could be the key... my little guy likes this, and my cousins little guy learned how to ride on this as well (he was 3 and on his own) www.thebiketutor.com
, this company recommends only teaching your child how to ride with their seat. Short rides 20 - 30 minutes and in safe places. When you take them for little rides they really get the feel of the bike and you can focus on teaching them road safety!
There was a moment after my cousins little guy was riding on his own, out front of the house, and a car was coming and he did't have time to go out to get him...he got off his bike and walked to the side of the road and waited for the car to pass. My cousin was so happy that he was able to witness his safe riding technique in action.
Our children are precious so give them good knowledge and do your best to help them make it safely. When riding a bicycle there is always a risk of injury or accident, so choose your path wisely and safely, and actively teach your children to do the same.