Roper Elementary School suffered thousands of dollars of damage overnight, police said.
The damage was discovered at about 3 a.m. Tuesday when Lincoln Police and Lincoln Fire and Rescue responded to a pulled fire alarm and found the school in disarray.
Lincoln Public Schools officials estimate it will cost $10,000 for labor, materials, repair and replacement items.
Officer Angela Sands said fire extinguishers were sprayed, vending machines were looted and damaged, and windows and clocks were broken.
Flags, chairs, cupboards, books and other supplies were thrown around the school and damaged.
In an email sent to families of Roper students, school officials said crews worked Tuesday to clean up and repair damaged areas of the building.
Although originally the school had planned to have an ice cream social Tuesday night, it was canceled Tuesday afternoon because of the high chance of rain.
Summer school and summer library hours will go on as scheduled Wednesday. Yearbooks will be available for pickup from 10 a.m. to noon during summer library time at the school.
Sands said the school, 2323 S. Coddington Ave., doesn't have video cameras and it was unclear how someone gained entry into the building.