6x1 part dos.....

Being as that I'm probably not the most in tune with experimental film, I wouldn't know much other experimental projects that could be done than what we've done so far. I will say that no matter what, a fort must be built in every 6x1 class. that was awesome.
Having said that, maybe a sort of "Given" footage project could be done. Where you give us a certain amount of film from random other projects or stuff that you've done, and we would have to create something out of it. It kind of resembles found footage but it provides a nice little artistic constraint on our part.
I would say more working with actual film. Even just using the small regular 8 that you had was pretty fun and interesting. Maybe even incorporating a little more animation would be fun. Learning a little after effects or flash would be cool. 1 minute animations can always look pretty sweet.
Maybe even doing an interesting "star wars uncut" type of deal but with a different movie. You could cut up a certain scene into 16, 1 minute segments, and each student (or pairs or whatever) would have to recreate that scene, and then you would attach all the segments together.
Other than that I can't really think of too many other 1 minute productions....I think part I of 6x1 covers quite a bit.