It might also be good for students to have practice staying in time with another musician and being sensitive to somebody else’s expression while playing. A key to good chamber music is whether the players are listening to each other or just each playing their part, coincidentally at the same time as a few others.
I remember once where my first teacher, as homework, had me write out a brief musical phrase of my own invention. As part of the next lesson, I played some variations on it, using minor keys, lever trills, glisses, etc., as some