Divide players into two groups, one for each station.
Sequence (Station 1)
Number the players in each group.
Players pass back and forth while moving around their grids.
The coach calls the name of one player, who prepares for a high ball in the air. This player has to head the ball to the next player in the sequence.
The first team to complete the task scores one point.
Sequence (Station 2)
Two players stand outside the grid with one ball each, and two more stand inside.
The players inside the grid call for serves to their heads. They either head the ball directly back to the server or control it with their heads and then pass it back.
Players switch positions after one minute.
Tips and corrections
Players at Station 1 need to find the best way of passing to whichever player is called to receive.
Because the main focus at Station 2 is accuracy, players should rest between serves.