I'll add another recommendation for Scheme. The concepts in SICP map very well into Scheme, whereas I can only imagine them being awkward and non-idiomatic in JS. There's lots of passing around first class functions and use of recursion.
One of the two professors (Dr. Sussman) that give the lectures in this series is a co-creator of Scheme.
One of the two professors (Dr. Sussman) that give the lectures in this series is a co-creator of Scheme.