Finally, I've heard that some of the high school tournament games draw extremely well, though I haven't been to one at the Convo for a number of years.
I've seen the CONVO packed to the light green seats just in the past decade. I know that Chillicothe, Logan Elm, and Greenfield at one point brought huge crowds in D-II, but I think it has to do with recent success on the ball court (Greenfield has died down since graduating Dante Jackson of Xavier fame.)
But we must also remember, the seats for high school games start at the lower bowl as they don't bring out the reserved seats, nor the student section seats. Even though there were a lot of people in the upper bowl, I'd say that very few of those games exceeded 7,000. You'd have to ask Lou or someone in the ticket office (most likely to know) for specific numbers.