We faced a variety of challenges trying to get through our first real modeling-style discussion. Essentially, they all boil down to respect.
2nd hour: Things went fairly well. A selective sample of questions were presented by groups and students asked insightful questions while I jotted down bits of what they were saying to highlight the key ideas.
5th hour: A struggle. 3 students had to be sent to the SRC (Student Responsibility Center) for continuously disruptive the discussion. Things got better after that, but in general the students are fighting the transition to becoming active learners.
6th hour: After the difficulties in 5th hour, I was a little frustrated. I noticed that when I stood silently in the center of the class, the students knew I wanted them to quiet down and generally did so. But as soon as I started talking again (even just to give instructions), conversations would immediately break out all over the room (35 students in 8 groups). I pointed this out to them and explained that I was going to remain silent for the rest of the discussion. I didn't really think this idea would work, but I figured it was worth a shot.
It was weird - for a second, they actually looked like they were going to pull it off. A few natural leaders took charge and would call out whichever group was next, the group would present, and they would move on. Sadly, no one was really interested in ensuring everyone understood the work and students were visibly (and audibly) frustrated at how everything was rushed at that i wasn't "teaching."
I let them finish and asked how the felt about what just happened. They hated it, with 'it' being the fact that everyone wouldn't quiet down and let any progress occur. I explained that if we switched back to a traditional classroom, nothing would change (I know, I've done it both ways). The difference is, *I* would get to be the focus of their disrespect instead of each other. The amount of learning doesn't really change, but they're happier because they're not responsible for the classroom environment.
For the last 15 minutes, I moderated a MUCH more respectful discussion of a few key problems and we called it a day.
I faced similar struggles when I adopted modeling in physics last year, and I was concerned that 10th graders just might not be mature enough to handle a student-led environment such as modeling requires. Now I think they *can* do it, but it's going to take some work. I'm not entirely sold on my 5th hour though - the big difference I see between "regular" and "honors" is behavior and maturity - not intelligence.