I’ve got three things to say: Substance, substance, and substance.
Frum jews are the masters of hyperbole. We manage to say wonderful sounding things which are so broad they mean nothing. (Like the previous sentence, for example.)
Say something substantial. Don’t say “a pleasure to have in my class”; say “asks good questions which show he is listening and interested.” Don’t say, “has wonderful middos”; say, “includes the less popular classmates in games and jokes.”