Not sure what you guys are using to track all of it, but maybe a simple web app would help you out. For instance, an email address would be attached to a "level" (so you guys could input your previous members and attach what level they're on so if they sign up with that same email it'd be aligned).

People could sign up and post their solutions, and others would be able to validate entries of levels below them (so someone on level 3 could validate a level 2 submission). Or hell, the webapp may even be able to validate some of it (obviously not entries where you paste code, but things like "Decrypt !4321hj4123$@!#$" could be automated).

This way, you could submit solutions via your login (attached to your email) and people validating the entries wouldn't be able to see the email address, just the answers, and could comment on the submission.

Sorry, this was a bit stream of consciousness. If this was particularly barebones, you might be able to slam it out in not too much time. If you don't mind PHP or Common Lisp in the backend, I might even be able to help out a bit.