I like to have young ensembles do unison scale warm-ups. Doing just one at the start of a coaching or used as a break in the middle is a fun activity and gets students involved in making decisions about the music. It's also a great time to work on matching intonation and developing a group sound and pulse.
Students can pick the key (it's a good time to review key signatures!) and one or two different musical elements to incorporate. As they become more advanced, more elements can be included. These elements would include things like: articulation, dynamics, melodic shape, balance, character/mood, tempo or any tempo fluctuations such as ritard or accelerando.
Other exercises for innovative coaching covered in the article include breathing, setting tempi, ensemble dynamics, awareness, focused listening, rhythm games, and singing.
Previously on the Collaborative Piano Blog: