I'm sorry things are so frustrating right now. Hopefully, with the GIEP, things will start falling into place better. Your biggest frustration (seeing that your son is not challenged in school) is my biggest worry for when DS4 starts school. I wish you luck!
As an aside about charter schools, I recently became involved in a STEM charter that's set to open in fall 2009 for kindergarten. It is not a gifted school, but I think its learner-centered philosophy, along with the STEM focus, would be better for our DS than our local overcrowded schools. It's 40 minutes away from us, so we haven't completely decided yet, but it's sort of nice to be in on some of the planning - i can always give my 2-cents. I'm figuring that we're going to have to squeeze as much out of any school we go to, no matter what it's designation, so i'm just looking for the one with the most juice. (And homeschooling will be our backup.) FYI - I'm thinking that the start-up charter schools won't have much press, since they don't have funding yet (we stumbled upon it). I guess I just wanted to say there might be some things out there that we're just not aware of yet.