A Cedar Falls elementary school is making some changes after two kindergarten students left the building while switching classes. Principal Steve Harding at Orchard Hill Elementary says the girls walked out of the building undetected last week and weren’t discovered missing until neighbors saw them trying to get into one of their homes. The students walked more than a mile in cold weather before they were found. Harding says the art teacher thought the girls were absent, and it wasn’t until the class went back to homeroom that they were discovered missing. Now, district officials say Orchard Hill teachers will go through head counts between classes and check all students for passes when they are seen in the hallways. The school also plans to put an alarm on the door and make sure all visitors are identified with a pass.