After a few years of tricycling (injuries: 4 stiches in the skull after unsuccesful scaling of staircase) I learnt how to bike at the age of 5 on a girlie singlespeed with no stabilisers. The bruises on my legs would have rung alarm bells with social services.
My first close shave was a few months later, playing on a ramp at my dads office (a country manor in a small village). As I rolled down the ramp, I suddenly found a huge Vauxhaul car bearing down on me. Managed to keep my wits and stay out of harm, but the lesson was learned. THEY are out to get you.
My first real new bike at 10 was another singlespeed, a Raleigh Rodeo, 24" wheels with dynamo lighting, saddlebag, fenders etc. It was my daily transportation for a few years, and gave me freedom to go where I wanted when I wanted. I dont ever recall having a problem riding on the roads, but I did do a cycling proficiency course at school.