Has anyone mentioned Knowing Better yet? Guy makes fantastic videos explaining a wide variety of topics. Some of his latest ones have been very in depth analyses about periods on American history, though he has covered many more subject as well. Highly suggested if you like long form content.

Another channel that I love is Captain Dissilussion. A guy dressed as a superhero breaks down the special effects behind hoaxes and viral videos, usually with a lesson in the end. Great channel even if you don't know anything about special effects, you can learn a lot about how effects are done, how to spot them and then be surprised when the guy flexes his own (better) version of the effects at the end.