They don't want him to have to go to another building or to be in class with the middle-schoolers at his age. Of course, it just occurred to me this very instant that it's the same kids he's in 5th grade class with this year, LMAO!
I'm laughing with you - although the kids do get scary when those hormones hit! But I really don't think that you should let the school off the hook so easily - afterall - what about the year after that? Unless your kid is a total 'self starter' I would try to keep him with other children - I have just seen so many 'independent study' programs fall apart, or 'get casual.' You child deserves to be taught, although we would settle for protecting our child from mistreatment at times.
If you do decide to do an online curriculum - I've seen folks be very happy with
http://www.artofproblemsolving.com/Classes/AoPS_C_About.phpThey say it's for 6th grade, so it's possible...
Love and More Love,
grinity