I think that I began shaving on a regular basis around 14-years old (perhaps I fiddled with it unreligiously at 13, or even a short session at 12), but the regularity was dictated by /if/ I deemed the situation to need it, hah. In other words, the summer generally called for it, while the winter did not.
I would have to say that the majority of girls begin in the early teenage years (13-14), or just before (12.)
My parents never really told me a time in which I could begin... so I slowly started myself; they did not seem to mind or say anything about it. One day, it all just became common knowledge and my mother would ask if I needed new razors.
I am primarily of Italian descent (although, I am not saying that all of said ethnicity are equal to this, mind)... consequently, I possess (and have since a child, to an extent) quite the thick, dark growth that must be tamed!
I have never truly understood the strict, outlaw of shaving by parents... how is it inappropriate? If she was requesting to lather on make-up and revealing clothing: I would then worry and take your side.
What's funny is my 'mother' taught me to shave below the knees. Then one day in high school, I was on the bus to go home, and I saw this girl get on and with the sun shining on her legs,I could see all the hairs on her thighs. I was like,ewww. From that point on,I started shaving my thighs as well:)
When there was a need to but I don't recall when that was.
When I was 10. Which seems early in retrospect, but I was one of the last girls in my class to do it. Maybe cause I was in a class with mostly Italians and Latinas (lol, Catholic school). Also, being Italian, I myself am quite hairy so I felt it was a necessity at the time.
My parents were against the whole shaving thing until I am older, but I was a rebel and started shaving secretly when I was 13 years old. But they found out the upcoming summer. They were so pissed off at me that they went through my whole room and threw out every shaver, shaving cream, and waxing kit they found. Every 2 weeks, they would ask to check my legs, and underarms. It totally sucked for a few years cause in senior high, I was the only girl who didn't shave the underarms and legs. Talk about embarrassing. But since I am 21, I can shave or wax anything I want cause my parents can't control what I can and can't do. But still today, they hate the idea of me shaving or waxing.
I think I was 12 when I first shaved my legs. I just decided to try it, and then I felt guilty about it (my mom doesn't shave), so I had to go tell my mom what I did and that I was sorry. She didn't care at all, haha, she just told me that it was okay, and that some people did and some people didn't, and if I wanted to that was fine. :-)