Have students scatter in the playing area. Tell the students that they are only allowed to carry ONE beanbag at a time in their hand. Have students throw with their non-dominant hand. Have tagged students balance the beanbag on their head until unfrozen. Have extra bean bags on hand just in case.
Students have a tendency to run after stray balls with their head down.
Make sure your students have a good grasp on moving in general space with others in a dynamic setting. Start the activity off by walking. Then change to more difficult locomotor movements as you are satisfied with safety.