I went to school in Berlin (though i'm 32 now) but my nieces and nephews are in school now and the schools in my opinion are very good. Some of the teachers who taught me are still there. I live in FL now but am moving back this summer. I have a daughter who will be attending high school in the fall and she is blind. I notified the school system and they were on top of getting things prepared for her to attend since she will be the first blind child attending school there. I was quite impressed with their quick response. As far as sports, I don't know if they are ALL school related since there are a lot of community based kids programs too but my nephew plays hockey in the winter and baseball in the summers. In high school, i remember track was popular along with hockey, field hockey, softball (for the girls). I don't think they have wrestling or football though.
If you need any info about the town at all, i'll be free to share. I was born and lived in NH until i was 18, moved to FL and now going back to be with my family again this summer. It's a nice little town to live in especially if you have a guaranteed job waiting for you. That seems to be the biggest problem up there is lack of employment.