You shouldn't shake the cage of your classroom pet.
Tim stands at the cage where the classroom gerbil lives.
Tim wants to make the gerbil move.
Tim talks to the gerbil and watches for a while, until it begins to move around on its own.
Tim shakes the gerbil's cage vigorously to get it to move around.
The gerbil grows to trust Tim and the other children and it is friendly and sociable with the class.
The gerbil becomes frightened and starts trying to get away from the children whenever it sees them coming.