D.P.
What does he like?
Is he into Super mario Bros Wii games, like my 7 yo? If so, what about an at-home Wii tournament/party with good old fashioned balloons, pizza, cake and ice cream, chips and pretzels? Might be a welcome change from all the über-theme parties!?
IME, boys of 6-7- and 8 just want to hang out & get goofy--ride go karts, play games, swim, run around.....