I hate to give gift cards.. it is a personal thing for me. I don't know why (maybe because I can't get them on sale).
I was reading up today about this same thing:
binoculars (if they are into sports to take with them to the games)
sweatshirts (maybe their favorite team) my 12yr lives in sweatshirts
board games (help get them off the electronics)
books (maybe relate it to their favorite sport etc) My DS is ready the Twilight series right now. Also "Down the Rabbit Hole" it is about Alice in Wonderland (he really enjoyed that
Hope this helps! Let us know what you choose.