No one noticed the lost computers until Thursday of last week when a teacher went back into the school and discovered they were missing from the classrooms, said Danville Police Sgt. Kevin Daley.
Janitors at Green Valley Elementary had previously found the doors forced open; they repaired the doors but didn't call police.
The theft occurred sometime after the last day of school June 24. There are no suspects.
Schools are vulnerable in the summer months, Daley said.
"Obviously the bad guys know school's out, and schools have computers," he said.
The estimated value of the stolen computers is $8,000.
On Monday last week, an unknown suspect attempted to burglarize two offices in the YMCA building at Hap Magee Ranch Park.
At 9:20 p.m. the burglar used a pocketknife to jimmy the lock and kicked in the office doors. Papers were strewn about but nothing was missing, said Daley.
"It was apparent they were looking for something but they didn't steal anything," he said. "They basically vandalized our Hap Magee Park."
He guessed that since the gates are locked at that hour and the burglar was on foot, he or she was looking for cash or something easy to conceal in a pocket.