We're nearing the end of summer and that means it's time for back to school shopping. If you're the parent of a teen though, you know that this is an especially trying time of year. We're here to help. These are the seven hottest Fall fashion trends for teens this back to school season, according to Seventeen magazine. We've seen these styles before but they all have a new modern twist to them for today's fashionable teen. Imagine how impressed your teen will be that you know …