[Air-L] policies on students and social media platforms

I've volunteered to spearhead a department initiative to draft an ethics document. Part of it would involve whether it's okay to require students to have or use online presences on social network sites or blogging platform for class. I have my own complicated feelings about this (which are rather site-specific and related to privacy controls and other factors), but I'm wondering if there are any academic departments out there that have grappled with this issue and have policies about it. Thanks, Holly