The CMU class looks interesting but it seems the assignments are behind a login. A list of classes that have more open content - https://github.com/prakhar1989/awesome-courses#systems

I took 213 at CMU. Can't recommend it highly enough. A lot of other intro systems courses are based off that. It is a prerequisite for most classes moving forward at CMU. The textbook is also available online as a pdf (Google it). First 2 or 3 labs deal with bitwise, assembly (buf overflow attacks - bomb lab), then cache lab (matrix multiply performance), then signals, then implementing malloc, and finally using pthread API / threads to create a proxy server.

Actually you can find similar versions here. http://csapp.cs.cmu.edu/3e/labs.html

I think you can get self study versions of the assignments off the textbook web page

Sorry for asking dumb question, but after looking to their website I couldn't find lectures for Operating system course. Where could I find them? (I am talking about CMU course)

Does it need to login to watch lectures ?

Its way better than Udacity's intro to os course. Just read through all the assignment descriptions, and you'll get an idea of how much you're going to learn.

Wow, I've read about half the intro to computer systems textbook and had no idea there were lectures online. Very exciting. Thank you.

I've been going through some of these. These are great. Thanks for sharing.