My younger son has a male teacher this year. The teacher likes to play the guitar. I got lucky.... went to an artisan fair and found a lovely wooden bookmark with a guitar miter-cut into it. So cool! And my son says he liked it... bonus!
Sorry, that doesn't help you much but I'd try to find out what the teacher likes and go from there (as in if a sports fan, make something sports themed or if a music fan, make something music themed)