The materials are interesting and thought-provoking to me. However, it's like pulling teeth to get the students to do any of the classwork. If the assignment is to be done for homework (ie. research or bring in something), it doesn't happen. What have you done to get the students truly engaged in the lessons?

Thank you for your post!  Some suggestions and comments:

• Make sure you are using the web sites provided at the beginning of each unit to capture student interest in the topic as quickly as possible. Perhaps THEY can look up the links and share the information with the group(s), too.
• Speaking of that: Are you using small group instruction at some points in the instruction?  Give them the opportunity to work in a smaller setting to work and discuss what they are learning about the high interest topic (even if it gets a bit loud sometimes).
• IF you decide to assign homework based on the unit, make it experiential in some way rather than merely a "read and answer" format.  Homework in general today seems to be problematic for many reasons that have nothing to do with student apathy. Therefore, it needs to be seen as truly based in reality in some way.
• Tie the unit immediately to the Authentic Assessment! Get them thinking about ways to develop their project for that Assessment from the beginning of the unit, and perhaps give small assignments along the way to work on that.
• Allow carefully selected (by you!) students to teach small segments of the lessons, such as vocabulary or a short response writing prompt.

I hope some of these suggestions have started your creative processes!   Thank you for what you do for students every day....you ARE making a difference, even when you think you are not.