What about a series of lessons that is, in effect, a writers' critique group? You could start by posting one of your old Challenge entries and do a self-critique. You could point out certain things you were trying to accomplish with the piece and tell whether you think it worked well or not. You could point out particular techniques you used. The possibilities are endless. Did you have a hard time editing to length? Did you struggle with the opening? The ending? The title? Did it flow (comparatively) effortlessly? Was it a real struggle? Was there one critical change that made the piece so much better than the first draft? Is there a flaw that you see now that you missed when you submitted? Are you uncertain about the effectiveness of something? You could also ask us our opinion about thigns.
Then we could agree or disagree with your self-critique, ask questions about it, make suggestions, add our critiques, let you know that you helped a light bulb go off for us, answer the questions you posed. Again, the possible responses are endless. Plus, once it gets rolling everyone can interact, not just with your original self-critique, but with each others comments, too.
Then after the first week (or several) you could invite us to submit one of our old entries and our self-critique. Of course, you would only be able to use one of our entries per week, so volunteers could pre-submit to you and you could pick one—maybe first come, first served; maybe an entry that is especially strong; maybe one that has some element you especially want to interact with.. Then everyone else (with you as the teacher going first) could play our normal role.
One advantage of this is that you would have a ready made starting point each week (whether you were self-critiquing or critiquing one of us). If you didn’t get enough (or any) volunteers or if you wanted to demonstrate something in particular that week, you can use one of your old entries again.
Another advantage is that this series could be as long or short as you want. It’s not like the challenge entry criteria where you had 10 (is it 10?) items to cover. With this you can stop at any point. Or if it’s popular, continue it for a long time.
Another advantage is that it should be very interactive, since we could all interact with each other and with you.
I know this is different, but it’s the only idea I’ve had so far.
"When the Round Table is broken every man must follow Galahad or Mordred; middle
things are gone." C.S. Lewis
“The chief purpose of life … is to increase according to our capacity our knowledge of God by all the means we have, and to be moved by it to praise and thanks. To do as we say in the Gloria in Excelsis ... We praise you, we call you holy, we worship you, we proclaim your glory, we thank you for the greatness of your splendor.” J.R.R. Tolkien