I studied Haskell in college (with the Gofer variant), and it was GREAT for learning practical functional programming.

We didn't use monads though (they weren't in widespread use back then), so we had to learn the accumulator-parameter pattern and tail recursion the hard way.

Learning my foldr's and foldl's and zipwith's gave me confidence that almost any imperative programming can be equally represented as a recursive function, which is an important lesson for someone who had only learned about traditional imperative programming and OOP up to that point.

Of course, a proper course should center around algorithms and recursive data structures where functional programming shines; it should not begin with building business application logic, for which a classic language may have a gentler ramp-up.