1. Invert the classroom. Definitely too big a project to do all at once. Maybe try for once a week in one class?
2. Class blogs that students contribute to and comment on.
3. Send assignments and reminders as text messages.
4. Send assignments and reminders on Facebook.
5. Use polleverywhere in class more than one time as a novelty.
6. Survey students at points throughout the year to prompt them to reflect on how they learn.
Obviously I can't do it all because, my goodness, those poor children. I feel a little like I am holding a bunch of hammers, in search of a nail. Are you using any of these successfully? If so please tell me about it.