I remember learning to ride a bike as a kid and I remember having to use training wheels--they're like the braces on your teeth, but for your bike. I hated training wheels and I was so glad the day we took them off and I never had to relay on them again.
Years ago my oldest son got a bike when he was fairly little. It was a bike his cousins outgrew. He had a tough time learning to keep his balance on the bike--pretty much a "must know" to be able to ride. He got it after a while. A few years later our next two kids were of the age to get bikes. Around the same time, we bought a couple of razor scooters and soon the kids were zipping around the street on the scooters.
Then a funny thing happened. When the kids had mastered the scooters, they hopped on their bikes sans training wheels and they could ride. There was no running behind the bikes by dad with the younger kids. They had learned balance on the scooters and without even thinking about it, they could ride their bikes.
And now our youngest son is of the age where he wants to bike around. We picked up a used bike that fits him, but we don't have any training wheels. So for the past few days we've been taking the scooters out and learning balance. He will validate (or destroy...) my "use-a-scooter-to-learn-how-to-ride-a-bike" theory. We'll see what happens.