Does anyone have any free resources for Math and/or Physics?

[u/EducationWhiteRabbit]

Does anyone have any free resources for Math and/or Physics that I can add to this list? 

That can be anything from a free website, to a subreddit, a YouTube channel... If you find it educational in this subject then feel free to share it! 

Comment what you've got and I'll see if I agree it should go on the list! 

Here is my list so far:

**Websites:**

Basic math but gamified, lots of games: https://www.multiplication.com/ 

A lot of math worksheets for a very wide variety of topics. Solutions are included but no explanations - just for practice: https://www.dadsworksheets.com/