Jason, I do check more often than I tell students, but I also run a Frequently Asked Questions Discussion Board that other students can answer for extra credit. After the first couple of weeks, it seems to take of itself, although I do check briefly each day. But, briefly, as other students are doing the work for extra credit. And, I mean minimal extra credit. I give somethiing like 5 points extra credit out of 400 for the total class. Once a student answers another student's questions on the FAQ discussion board and it is correct and complete, I email that student thanking them for taking the time, etc. This encourages them to continue. It works for me.