Hi, as an introduction, it would be a good advice to first look, if you did not heard of it yet, at what the 42 school is: http://www.42.fr/42-revolutionary-computer-training-free-and-open-to-all/

(TL;DR: "unique pedagogical approach and accessibility to all, completely free of charge, 42 is the most daring response yet to the challenge of information-technology skill development",
"Innovative teaching methods in technology training: Peer-to-Peer learning")

​The school aims to teach a general knowledge of computer science, but does not provide a Haskell course yet. ​The exercices and projects are built by students, for students. I love haskell and I'd be really happy to teach that wonderful language, and I'd love to hear your suggestions. I was thinking of the haskell's hard learning way. (I gotta say, the school's pedagogy is pretty sadistic).

• Recode List, (,), Either, Maybe and their functor/applicative/monad/etc instances (implying recode those data types first)
• String manipulation (basically recode Data.List). Any ideas for prevent students from just copy pasting the hackage code source?
  
• Red black trees are fun, aren't they?
• Some kind of AI to solve, for example, Rubik's cube

One other thing, this may be very sadistic, but I would like to ask what do you think of allowing ONLY pointfree? It may end-up by having different answers and promote beautiful and concise code. Please expose your ideas, everything is feasible, bonus added to traps, hard to solve problems, and everything that may lead the student to think a lot.

Thanks.