Adrienne, My IT folks are able to block certain sites if I request them to do so. Also, our institution has sites they block automaticall, and I need to request they open up certain sites from time to time as the need presents. Another strategy is to segment your approved witing time to align with a specific assignment, that will be graded, and has a fixed time limit. Afterwards or after discussion, additional segments can be assigned in a similar fashion. The purpose if to force students to focus where they will realize to get points for the assigbnments, they have to remain productive. Finally, you control the class, so it's resonable to ask to turn of the computers or to not go to undesired social sites. Barry Westling