Carey Gallagher began her senior year at Yonkers Middle High School in New York this week alongside 1,438 students, now all required to place their cellphones in a locked magnetic pouch. Yonkers School District purchased Yondr phone pouches for about 11,000 students to comply with the statewide mandate that bans phones in classrooms. The pouch, which students carry with them, is locked and unlocked using magnets affixed to the entrance of the school and outside the main office.