Ask HN: What are some of the best university courses available online for free?

The Science of the Solar System (Planetary Astronomy)

by Caltech Professor Mike "plutokiller" Brown

https://www.coursera.org/learn/solar-system

I really liked this course. Here's the blurb:

Learn about the science behind the current exploration of the solar system in this free class. Use principles from physics, chemistry, biology, and geology to understand the latest from Mars, comprehend the outer solar system, ponder planets outside our solar system, and search for habitability in our neighborhood and beyond. This course is generally taught at an advanced level assuming a prior knowledge of undergraduate math and physics, but the majority of the concepts and lectures can be understood without these prerequisites. The quizzes and final exam are designed to make you think critically about the material you have learned rather than to simply make you memorize facts. The class is expected to be challenging but rewarding.

It is also taught at Caltech, see https://mikebrown.caltech.edu/teaching/science-solar-system

gilbert strang's linear algebra https://youtube.com/playlist?list=PL49CF3715CB9EF31D. he has a few other linear algebra themed courses on there. very good because (1) he’s an incredible teacher, and (2) linear algebra is beautiful

Jeremy Siskind's jazz piano courses taught out of Fullerton College.

https://jeremysiskind.com/jazzclass/

This is a bit of a cheat because these courses are not free ($50USD for California residents and around $400 for non-CA residents) but they are so good that I had to mention them.

I am nearing the end of the Level II course and have learned so much stuff. They force you to do so many things that you otherwise would not do. Basically, ever week you have to post a video demonstrating what you learned from the previous week. And the video is in a public discussion forum with the other students so there is this incentive to do an extra good job. And he gives great feedback on your assignments.

I really liked The Theoretical Minimum lectures on classical and quantum mechanics by Leonard Susskind (suggestion: google up the guy, he’s cool) at Stanford. You can buy books, but the lectures are all free on YouTube.

Classical mechanics playlist can be found here https://youtube.com/playlist?list=PL47F408D36D4CF129 and then there’s quantum mechanics available too, should be easily discoverable. And also there’s just https://theoreticalminimum.com/

Not sure if they qualify to be a “true” uni course though, because in this case nobody’s gonna give you assignments and grades :)

I really enjoyed the free content on Udacity (https://www.udacity.com/). I'm not sure if it's "university" but their content was presented well and I came away learning new things about math, python and ML.