Ninth-graders design science experiment to test the effect of cellphone radiation on plants. The results may surprise you. Five ninth-grade young women from Denmark recently created a science experiment that is causing a stir in the scientific community. It started with an observation and a question. The girls noticed that if they slept with their mobile phones near their heads at night, they often had difficulty concentrating at school the next day. They wanted to test the effect of a cellphone’s radiation on humans, but their school, Hjallerup School in Denmark, did not have the equipment to handle such an experiment. So the girls designed an experiment that would test the effect of cellphone radiation on a plant instead.