Chicago police officers took part in an outdoor roll call at Harlan High School in the South Side Rosemoor neighborhood.
The event was part of Operation CLEAN, which stands for "Citizens, Law Enforcement And Neighbors."
Community policing members and city workers removed unwanted litter, trimmed trees and erased graffiti.
Operation CLEAN will be held every Friday through September in neighborhoods near various public schools.
The goal is to improve the quality of life by changing conditions that breed crime.