COLUMBUS, Ohio (AP) — Students in Ohio's largest school district were returning Monday to classrooms after members of the union representing teachers and other employees approved a contract, ending a strike that began a week ago. The Columbus Education Association's nearly 4,500 teachers, librarians, nurses, counselors, psychologists and other education professionals on Sunday voted 71% to 29% to approve the new three-year contract with Columbus City Schools. The pact calls for 4% raises each year of the contract.