While surfing the interwebs, I came across this video series about functional programming with Javascript by Mattias Petter Johansson. I liked them because he explains concepts at a easy-to-follow pace with clear examples and a smattering of humor here and there.
I just binge-watched 6 of the videos (each one’s around 10 min long), and it looks like he’ll be releasing 1 video per week. So if you want to improve your Javascript skills, check these vids out.