> (From experience) providing solutions interferes with the learning process of my own students at Illinois. I have to change up homeworks and exam questions every semester, because otherwise students will look up and copy/memorize the answers instead of trying to figuring them out, which means they do worse on the exams where they HAVE to figure things out.

While I understand the desire of a professor to help out their own students, at what point does this become a matter of individual responsibility? Shouldn’t it be the student who refrains from memorizing answers?

When I took my algorithms course, we had a reference textbook with questions at the end of the chapter, but no solutions. Some people at the beginning of the semester tried to crowdsource the answers using a Google doc but that effort failed. It didn’t really matter though, since our homework and exam questions were always renewed each semester through the work of course staff and the instructing professor. In hindsight, I may have taken this for granted as it seems other schools don’t have a “training” and a “testing” set of problems - I would say having both is better than only having one.