Octopus

Select one student to be the octopus and place them in the middle of the gym.
Have all other students line up beside one another at one end of the gym, facing the octopus.
When the octopus shouts “Octopus,” all of the students try to run from one side of the gym to the other.
The octopus is allowed to run anywhere in the gym.
If a students is tagged by the octopus, their feet become frozen to the floor and their arms stick straight out: They are seaweed.
For the following rounds of play, the game gets harder as the students who have been turned to seaweed reach out and try to tag students who are running by.
Remember that seaweed students CAN NOT move their feet in order to tag a passing student ( you might want to let them turn and face the line of students after each round, and just have them re-glue their feet to the floor once they have turned).
The last student(s) remaining at the end of the game gets to be the octopus at the beginning of the next game.