Another day, another gift guide! Today's treats are all for teenage girls. Shopping for teenagers can be tricky, because yesterday's girly girl might be today's goth—or vice versa. But when you find the right gift, you automatically become the coolest aunt/sister/mom/lady in the world. I've compiled some ideas for you along with a little advice: If you're not sure whether the teenager in question is wearing makeup (or is allowed to), check with her mom or dad first.