Being a hearing parent of a deaf child who is just beginning her student career, I can already say I am not a big fan of mainstreaming for Deaf kids.
My daughter (bilateral severe-profound progressive, aided, no speech, 100% ASL) turned 3 in December and transitioned to the the public school program. Currently she is in a classroom of 8 (ages 3-5, varying loss) with a teacher and a paraprofessional. Of those 8, she is the only child who signs. The other children do not sign to her. (They sign in group, while doing activities, etc., but not as part of regular communication) They talk at her, she signs at them and no real communication happens. The teacher and para use pidgin sign while speaking to communicate with all the children. None of this was a surprise. I was well aware of the specifics of the program before she started. It is still a very good program and the teacher is beyond amazing, but it is not a good fit for my daughter's needs.
I am lucky enough to be able to watch class now and again, see how things work. What I see is my kid's playing next to the other kids, often doing the same activities, and no incidental communication. The other kids are chattering away and DD's oblivious to it all, not participating/understanding. The teacher and para do help and terp for her, but I am a realist. There are just times they can't be there, in her face, telling her what's going on. After all, there are 8 kids (2 with severe disabilities that require extra attention). What's happening is that DD's not making those early connections. She's missing a big piece of the socialization puzzle. She's not making friends, listening to other's ideas/thoughts, connecting with them.
Looking down the road, I can't help but think it will only get worse. She will be moved out of her exclusive D/HH classroom and into a mainstreamed Kindergarten with an interpreter. A classroom with even fewer peers for her, if any at all. A place where she can't chat with the kids at recess without an interpreter 'in the middle'. A place where sign is not part of the curriculum and grades DO matter.
We have already decided that she will go to the school for the deaf. If we can't move before then, she will start boarding there for 3rd grade. (not at all comfortable with her boarding before that) We really hope to be able to make the move long before that, though, as soon as this summer. I really would like her to be there for Kindergarten. Until that time, we will stay involved in our local Deaf community, take advantage of the Deaf Mentor program and keep tweaking her IEP to fit her needs.
**I do have a meeting with her teacher tomorrow to discuss the incidental communication thing, among other things.