The best decision I ever made was asking students to contribute readings and start the discussions. Just a quick thought about no assigned readings, though. I have found it useful to provide a few core readings AND ask students to contribute more to the mix. The core readings lay groundwork and give students hints about keywords that they can search. Sometimes having the whole of the internet as a playground is too big… they get stymied by too much from which to choose. Generally, I’ve done some reading in the content area and I have a good idea of some pieces that lay a good foundation. Good luck!