SALINAS, Calif. -

Teachers at Roosevelt Elementary School came back from the Labor Day holiday weekend to find their classrooms had been broken into. Sixty electronic books were stolen, and eight LCD projectors also were gone.

"The punks who did this, the thugs are taking away from their younger brothers and sisters and impacting their learning adversely,” said Jerry Stratton, assistant superintendent of the Salinas City Elementary School District.

Stratton said a group of thieves got onto campus Monday night, and broke in through the classroom windows.

"They know what’s in there. Is it an inside job? I hope not,” said Stratton.

But Stratton isn't ruling that out. When teachers entered the classroom, they noticed the motion sensors were covered with paper and kids' clothing.

This isn't the only Salinas school to be targeted. Last week, Lincoln Elementary was broken into twice.

"The second night they came back they actually used a crow bar and broke into a front door of a classroom,” said Stratton.

Those suspects made off with a laptop and projectors. The district already has security that patrol the schools at night, but now after the recent break-ins. they are looking for extra security measures specifically for electronic devices.

"In the meantime, we'll probably evacuate them to a central secure site -not in a portable,” said Stratton.

School leaders are considering a reward in hopes of getting back the expensive books, and bringing the thieves to justice.