A central Iowa high school has cracked down on students' excessive use of cell phones and other hand-held devices by banning them during the entire school day. Officials at Bondurant-Farrar High School say students can carry their cell phones in their pockets or purses, but they can't use them or even look at them. That includes between classes and during the lunch hour. Officials say the ban was in response to students' excessive use of the electronic devices. They also wanted to control cyber bullying on social media. Students face different levels of punishment if they disobey the rules. Some students have had their cell phones taken away for a short period. At least two students have received a tougher three-day school suspension.