A Batley classroom was cordoned off as students collected crucial evidence for their own version of Crime Scene Investigation.
Year four students at Warwick Road School pulled on their white forensic suits after being told an incident had happened in their school.
Pupils got to work collecting evidence from the scene and interrogating teachers, who were lined up as potential suspects.
The young investigators collected finger prints and a slipper as they tried to solve the mystery.
They were also visited by Batley Neighbourhood Policing Team, who gave them advice on investigating crimes and interrogating suspects.
The project, which will be concluded next week, is aimed at helping pupils with their literacy skills.
Year four teacher Safiya Laher said: “It was a real wow factor when they came in and saw the tape across the classroom.
“They have loved investigating what happened and trying to get to the bottom of it.”