In all seriousness though, Kfish's last post is right. 10 participants x 2 patterns x 1 of each pattern = 20 flies, but you have to subtract your own set (unless you want to keep two for yourself), so it's really 18 flies.
Everything looks good to me. A few suggestions, though. Assuming we get 10 players, that means we're tying 36 flies each. I'm fine with it, but some might find that to be a lot. To keep the work load down, I propose we do one "fancy" pattern and one simple pattern. I consider stimmies "fancy" given how complex they are. Simple is a relative term, but I'm thinking basic ants, beetles, houseflies, etc. How about the due date being the first weekend in June? That gives us 5 weeks to get them done and, assuming everyone is done on time, we'll have them back for the first week of the June openers.