I have taught FP to more than one thousand students over 5 years. For all of them, the language was OCaml (at several universities, in Paris). At the time and

I have taught FP to more than one thousand students over 5 years. For all of them, the language was OCaml (at several universities, in Paris). At the time and still today, I think that OCaml is a very good language to learn FP. Students that learn FP before any other programming language get it quickly, and others can compare and write both the imperative and the functional form of a given program. But as a whole, the installation is easy and uniform (which matters a lot when teaching) and the standard library sufficient for everything, as you never want to have a lot of dependencies for the same reason. Of course, OCaml has its drawbacks: A weird syntax, terrible tooling... but you don't really see that when learning programming concepts. The only students which complained were the ones which already spent a lot of time programming before class and trollers at the same time.