That's a very interesting learning resource. I wish something similar came for Scala or Clojure (as opposed to tryclj, which does not have all those "Learn" pages).
Here's a monstrous list of online sandboxed REPLs, i think the first group, codepad, IDEone, etc can do scala and clojure but probably you'll want to go with one of the one click donwloads like Haskell platform, the typesafe installer or leiningen, unless they've somehow developed a miraculous classpath hell resolver.
