Ask HN: Educators, do you use knowledge checks?

Hi, recently I've been trying to self-study Computer Science. The networking textbook (Computer Networking: a Top Down Approach) I'm using has a free online resource called knowledge checks (http://gaia.cs.umass.edu/kurose_ross/knowledgechecks/index.php) and I'm loving it <3. I find it better than normal assignments due to it's immediate feedback

I'm wondering if other educators make these kind of resources as well?