I love Processing Monsters, I think it's a great idea. I saw it on Code & Form last week, and immediately gave it as an assignment to the 2nd-year students who, for the most part, have never programmed before and had only 3 days to learn the basics. Using Processing Monsters as an objective was great, as it kept us focused on some very basic functions (ellipse, bezier, shape, translate, etc) but which can quickly get out of control without some methodology. Also, looking forward to ENIAROF in March, monsters seems an appropriate theme.
I made the mistake of introducing class/objects on the final day, in a pretty funny class on fur, hair and tufts which I'll have to reproduce in some form or other. I should have started directly with objects, as we did in the Algorithmic Design project we initiated last month in Orléans. In my experience, it's easier to learn class/objects from day 1, rather than day 3, or week 5. Once you've become lazy programming spaghetti code, it's too hard to break it off into objects. No matter how ugly it is, once comfort has settled in, it's simply too easy to get stuck in linear thinking. That must have something to do with the brain's natural tendencies. However, if you start from day 1, you stay organized, people tend to understand the code better, and probably can make cooler monsters. Alas! We did things ass-backwards, and the students' code mastery suffered as a result. But a few of the monsters are fun nevertheless :