I just discovered Rustlings, which seems to be a good way to learn languages. Is there something similar for OCaml? Or can we refer to Rustlings to bring more inspiration to the improvement of the Learn section of OCaml.org?
GitHub - rust-lang/rustlings: 🦀 Small exercises to get you used to reading and writing Rust code!
I have heard very good things about Rustlings and I would try to support anyone motivated to build a solid OCaml counterpart of it. To my knowledge this does not currently exists.
A while ago @gs0510 and @pitag started working on ofronds which aimed to be something like this, might make for a good starting point to build off of.
The idea: Have a rustlings style tutorial for OCaml. The tutorial walks the user through a list of OCaml exercises, the command prompt directs them to the exercise they are supposed to solve and then as they work on the exercise a functionality like
ofronds watchcan recompile the exercise and let the user move on to the next exercise.
Ooooh, ofronds! 
Yes, ofronds was a really cool idea of @gs0510’s and it was a lot of fun working on it together! However, none of us has time to get back to it. So, yes, please do pick it up whoever feels like it. I think the rustlings concept is a very nice way of getting familiar with a new language.