A US school is being rebuilt to make it more difficult for gunmen to kill students in potential mass shootings.
Fruitport High School in Michigan is the first school in America to be rebuilt with concrete barriers in hallways to hide from bullets.
The hallways are curved to prevent a shooter from having a clear line of sight during any potential attack.
Classrooms have also been redesigned so students can hide more easily in case of emergency.
Windows that look from corridors into classrooms will have an impact-resistant film on them and doors will be controlled by local school leaders who can lock every door across an entire district at the press of a button.