Students should be divided into groups of four for flocking and make a diamond formation like the image below.
One student (in this case A) will be the leader and face away from everyone else. Everyone else should be facing the same direction as the leader and trying to mirror or follow their actions. The leader can do one or two kinds of movement that the group has to follow. The tricky part comes when you switch the leader. In our case the leader turns to the left and so does everyone else, thus making the person to the left of the leader the new leader. The golden rule to use to know if you're the leader is if you don't see anyone else, you're the leader. Students can do this improvisationally to music or can spend time rehearsing it to a chosen song or one pre-selected.
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Think that this is an excellent group activity the whole class can participate in. I think that it promotes good teamwork skills and cooperation. Like mirroring it requires a lot of focus and body awareness to see what the leader is doing and to mirror them. Like mirroring flocking allows students to take on a more shared leadership and responsibility for their flocking routines.
Accommodations I would suggest for flocking include: verbal and non-verbal instructions, extra time, modifying the kinds of movements to be done in a group with a student who has a physical disability, set a time limit on the routine.