I am in a middle school with three choirs each having aproximatly 30-35 memebers. We have block scheduling so my students are in choir for an hour and 15 minutes three times a week. We currently are on narrow risers that take up most of the classroom. A lot of my students have issues when we are sitting on the smaller risers. I am thinking of moving to chairs for the majority of our rehearsals then pulling the risers out once we are closer to the concert. I guess my main question is, “Are there significant gains in switching to chairs, or is there not much of a difference?”
Interesting topic! I have noticed that some choirs in English churches use music stands that are all connected, so they form a kind of long desk, with each singer having room for their music. Some choirs stand to sing and use chairs just for breaks. My guess with middle school is that more movement is better for such a long rehearsal period. If your room can accommodate music stands and perhaps have an area for moving to experience the music with large muscles, that would be my first choice. It is hard to recommend a solution without understanding how the room is laid out.
Another option is three built in tiers which are carpeted. The singers can stand, or sit on the tiers when they need to rest or do some kind of quiet activity, like decode solfege or memorize a part. Some choirs I understand bring ear buds so they can hear their part on an ipad before all the parts are combined in rehearsal! But that is another topic.