What should I say if asked, "Why am I in the special-support class?"

Tell them, "not because you're inferior, but because it's a place where you can learn in a way that suits you." A familiar comparison helps: "just as glasses make things easier to see, this classroom has arrangements that make learning clearer for you." Accept, without denying, any sense of inferiority they feel (such as being different from friends), then look back together, concretely, at what they've become able to do in that setting. At an age when others' eyes matter, discussing with them how to explain it to friends brings reassurance.