I'd send a follow up email, this time with a cc to the boss of the AP, and just keep widening your field. Each time, mention the previous emails. "In follow up to my email of x date describing my son's difficulties last year...(substance)....If you aren't able to help me, please feel free to forward this email and let me know who I should contact to help my son have a successful school year". Always be nice, to the point, and even though you are moving up the chain, avoid threats, whines, or a mention of motivation (even if you are clear what it is). If there is nefarious motivation, you can get to it by just listing the facts out, as if there is innocent intent. The person who wants to help will pick up on it.
Well said.
