start driving? 15 1/2.
actually start driving yourself places even if you didn't own your own car? Not yet, but hopefully when I get my license, which will be a few months after I turn 16.
get a car? Probably when I can afford one. Most likely senior year or early in college.
start telling your parents where you were going instead of asking them permission? Well I still tell my parents about plans in a way that I'm kind of asking permission, like "So and so texted me about seeing a movie at 4:00, I can go, right?"
get your first boyfriend/girlfriend? Not yet.
figure out what you want to go into in college? Hopefully by mid-junior year or so.
start having to pay for things for yourself? Right around when I turned 15, but I get an allowance, which I just use for everything.
stop having a bedtime? My mom will often be like, "You need to go to bed" by about 10:30 or so on school nights, but I don't have a set time I have to go to bed, and she doesn't really force me.
get a cellphone? 12.
really start feeling like you're growing up? 14 or 15.
develop your current music taste? 15.
I'm 15, by the way.