I would check to see if the Maine Photo Workshops in Rockport are still running. Short of that, a lot of the colleges in Boston have pre-college programs...kind of a long haul, but traditional photography classes are getting harder to find.
In the interest of full disclosure I should probably tell you I teach in the program at the Art Institute of Boston from time to time.
There is also a school in New Hampshire called Kimball Jenkins that I believe might offer "young photographer" workshops. There is a similar place in Manchester that has gotten good reviews from previous students of mine, but the name escapes me.
Sorry for the jumble of information. I hope this helps!