The teacher calls out a number, a place in the classroom and a body part.
Students must get to that part of the classroom, meet up with the specified number of students, and place the specified body part out in front of them.
Anyone who doesn’t make it in time must go and touch all 4 walls of the classroom before rejoining the game.
So for example, if the teacher says “3, Desk, Elbow,” students must get to a desk with 2 other students (to make 3), and touch their elbows to the desk.
This is a great game for transitions between subjects.