My rehearsal that day went so smoothly. I felt like I was on my A game and my chorus was so well behaved. They were never an awful group but always chatty, bubbly and full of so much energy. At the end of rehearsal I remember thinking, "What was different today?". When I realized that it was the agenda, I tried it the following week, and again great results.
Now I don't claim that an agenda is the end all of managing a chorus or orff rehearsal but it is a great tool. My kids know what we need to accomplish and they can see how far we have made our way through the list. They are so proud when we accomplish everything and humbled when we don't. This is because what keeps us from accomplishing our goals seem to be behavior problems.
Agendas also help to define time for specific tasks, like signing in or asking questions. I have 3rd graders in my group and a lot of gifted students. If you know anything about having an after school group with these students, you know there are A LOT of questions! I have started a policy of not answering questions about concert dates, attire, etc. until the end of rehearsal. I usually leave about 5 minutes for this before packing up. We fit in the questions we can, the rest are left for the next day or an email from a parent. I have noticed that I deal with less of these questions throughout my rehearsal because it typically is part of our agenda for the day.
This has become an integral part of how I run my chorus/orff groups and I can't imagine life without it. The best part is, it takes less than a minute for me to do before rehearsal.