I like this idea, eco. My one caution would be to try very hard to get buy-in from the 504/IEP liaison, and discuss with him/her whether it will be most effective in that building for the brief checklist to "come from" the liaison or the parent, and how long of a checklist/comment form is the sweet spot for informative data vs teacher compliance.
We use annual checklist/short answer forms to collect teacher input for IEP development (and this input is legally-mandated), and it is like pulling teeth just to get those, even with periodic stern talking-to by the academic director (their direct supervisor). So believe me, this problem of teacher communication is not restricted to uncooperative sped departments. Find the allies in your building.
Re: DSM Dx. They don't really carry more weight per se in the school system, since schools operate under IDEA, not DSM/ICD. They do give you access to additional categories of IDEA, though, as they allow for the Other Health classification to be used, if no other one is more appropriate. This is generally applicable in the case that the DSM Dx is -not- "Specific Learning Disability" or one of its DSM-IV equivalents. Once SLD is invoked, the school system will use its own criteria for LDs, which do not have to be the same as the DSM.
