Birthday Party Suggestions--teenagers

Just friends????

That can mean alot. These days that can mean they just "hook up" from time to time with no committment. In that case, maybe a gift certificate at a nice restaurant so he can take them out to dinner...

Or, it could mean unrequited love. Then, give them nothing.

Or, it could be that they like him and he's not interested. Again, nothing, to not lead them on.

If they are just really close friends with nothing else going on, he should know what to get.