In professional development sessions with groups of about fifteen faculty and staff members once every six school days, we are wordsmithing challenges that we hope to integrate into the curriculum next year if not before. The groups for each specific challenge were formed in November, so in some ways it seems like we haven't made much progress yet in over two months.
To me it highlights the importance of getting the challenge right.
In the project I did last semester, the challenge I gave the girls was "too amorphous," borrowing words from our CBL guru Larry Baker. In effect, I was really giving each group the responsibility of forming their own challenge. I don't think it's a bad idea if time is not a factor. But considering the importance of a well-formulated challenge and the difficulty of crafting one (at least by those not steeped in CBL), I can see that next time I need to bring the students in a little farther down the road.