My good friend Eric Swanson (the reason I have been in Colorado since 1993, but that's another story) has posted a good tool on brainstorming that you might find helpful as you lead. It's an excerpt from The Ten Faces of Innovation: IDEO's Strategies for Defeating the Devil's Advocate and Driving Creativity Throughout Your Organization
I wish that I had read this before a lame learning group on the CityFocus strategy that we had this past week at DCC. We invited Eric but some other folks we invited took over as if it was all about them. Sure that has never happened on your team.