I suppose that is exactly the reason that they offer educational programs, but for my class size and the resources available for my classes I'm not sure that is available to me.
When I completed my degree and got the eventual one year look back survey, I actually called out the explosion in faculty electing to use third party services which weren’t vetted by or supported by the university. One of my chief complaints was that students had no recourse other than to agree to arbitrary terms and sometimes pay arbitrary amounts to companies that were clearly monetizing our data.
(Although that last part isn’t as much a concern here.)
I can imagine if I was required to use something that made my coursework public, I would have simply gone to the CISO Office or the Student Ombudsman if not offered an alternative.
We mostly use a locally-hosted jupyterhub, but for JS work often used other environments. For JS, we made the switch to observable from iodide (after it was wound down) and I think I will re-evaluate platforms again, including JS kernels in Jupyter.
I realize there's a lot of interesting ethics boundaries on public software projects during education. I've always been "pro-open science" that more student projects should be open source/allowed to be open source as "teaching tools in the round", but am sympathetic also to how easily that can be abused for cheating or plagiarizing. I think it is an interesting discussion with no easy answers.
If the terms of that program aren’t workable, they can lose you. But freeloading is almost by definition precarious business.
The usernames don't have to respond to a specific user on repl.it so I guess there's no violations as long as students don't use their real names.