Code Academy has some good free ones
It’s not free, but this book is where I go when I need to learn something in JS:
It’s well-written and explains everything from basic to advanced. I do a lot of Apple Core JS, and this is a great reference when I have problems.
Gradually, I’ve gotten to know a little more js, and now I’m better at translating from js for the web to what I need, especially if I’m just trying to figure out a particular function. But it took a while, despite already knowing a fair bit of python, and having used some other languages (php, lua, a little Java, basic, tutor, etc.)
I did purchase the O’Reilly book for my library and will take the CodeAcademy courses just to get a basic feel for the language.
Thank you all for your tips.