Not sure why my previous response wasn't posted, but I'll try again:

Thank you for your feedback! I didn't even think of our local HS (only 4 blocks away, has a GT program). And I LOVE the idea of this person being a "motivator".

I guess the only think I'm still balking at (and I realize it's entirely my own problem) is seeming like "That Mom" asking for a tutor for her super special snowflake 5 year old son. I just feel like I am going to turn potential applicants off by seeming like I am an overbearing helicopter parent, or like I am exaggerating my son's intellect. Any ideas on what to ask for?

Thanks again for your help! I am so thankful to have found this community!