I don't have a specific goal, mostly because I didn't have one at the beginning and never set one. I moved to my current town/school in first grade and knew I wanted longer hair (I had a bowl cut when I was 5, shoulder length in kindergarten), but without a specific length in mind, I just kept letting it grow, until it became my "thing" at school. I like it a lot and have no plans to cut it, but I'm approaching knee length (I actually hit it last year, but needed a trim to even things up, so was at midthigh at the beginning of the school year) and am not sure if I want it past that. I think was really got me was doing my hair for prom two days ago - I put in two small accent ropes, and I almost couldn't finish them because my arms didn't reach far enough! I want to be able to manage my hair myself for all but the fanciest hairstyles, so I think I'm about done. I'll keep going for length, since the last six-8 inches of my hair taper a lot, but I'll keep it about knee length through college, I think.

A side note - as a bored senior, I decided to bleach the tips of my hair and then dye them purple. While there was definitely damage from the bleach, I know that after a couple trims, maybe three if they're small trims, the damaged section will be gone and I'll still have long hair. I guess having hair this long gives me the freedom to play and do crazy stuff, which I would be more hesitant about if I was trying to grow for length.