The 52 Photo Challenge is great, and pushes us to expand our creative skills. Especially wonderful are the truly superb submissions by a number of students on your site. That by itself is worth the money.
But if there's a downside to the course, it's that students are naturally hesitant to be give any opinion on someone else's photograph that might seem harsh. The closest we have to an approval or disapproval rating is the number of likes a photo will collect.
With that in mind, I would like to propose the idea of a 52 Photo Challenge Workshop, where each subject would contain a detailed tutorial, and two or three videos and work-along files. The members would have a website where they would upload their own photos, telling other members exactly what they did to capture the shot, and how they processed it. Most importantly, others would be perfectly free to give an honest critique, regardless of how harsh their opinion might be. As you well know, photographers must have a thick skin, or they can't learn anything. The workshop would be a perfect setting for this.
The alternative, (and perhaps the one you might choose) is to list at the bottom of your weekly challenges where students could get much more detailed instructions on a particular genre, through books and videos, and then see what progress they might be making by the number of likes their photos earn.
Thanks for taking the time to read.