Have the children sit in a circle, and select some suitable instrument from the class percussion trolley. A tambourine is a good one to start with – if you want to make the game more of a challenge, choose some jingly bells:
It is very simple; the game is to pass the instrument round the circle, without making a single sound. You can have someone sitting in the centre, with their eyes shut (or blindfolded) who points in the direction of any sound they hear.
I sometimes use the idea of this game when putting instruments away, especially after samba. I save the ganza (shaker) group until last, and once everyone is ready to listen, they try and carry their instruments over to the instrument bag while everyone else concentrates to see if they can hear the slightest rattle. It is a good way of calming a class after a noisy session, and settling them ready to move to the next lesson.