T.F.
I have a 14 yr old very social girl. Sephora is a favorite place for the girls to get cologne's. A good selection of men's cologne is available there as well. Sephora also has good associates who know the market pretty well. We like the location at Watters Creek and Stonebriar Mall.
As for what the girls like.......Ed Hardy, Ralph Lauren, Calvin Klein
All of the above can be found in men's selections. Also, i've heard a couple of the girls mention AXE as being a good one. It can be found at Target.
You don't have to get the largest bottle of any of these selections. A lot of the teens have 2-3 favorites and switch off. I usually purchase the smaller bottles because I know my daughter's taste changes a lot. (EX: she may be a nothing but Ed Hardy for a month and then switch to some Victoria's Secret scent for a month) I guess its a teen thing.
Good luck!