CHICAGO (CBS)– Twenty Chicago Public Schools lost power Monday and the school community is concerned about the lack of warning.

Despite the power loss, Shields Elementarty was the only CPS school that had to move students to another campus.

A downed tree blocked the path into Norwood Park School and power lines ran throughout neighborhoods, while Com ED crew worked to restore electricity.

Fewer than a quarter of the 430 students enrolled even showed up to Norwood Park School.

Some CPS parents and students complained about a lack of warning.

Debra Daniel sent her two 9th grade daughters to North-Grand High School as usual. They arrived to find the building without power.

“We didn’t get a warning,” Daniel said. “I would have preferred a warning because that would have helped me out. I was actually looking for CPS to close the schools, all of them. But, that didn’t happen.”

Anthony Czech, a North-Grand High School history teacher also walked into the school Monday morning, without warning of the power outage.

“We were told we had no power, so students were told they could stay and they’d have a place to grab breakfast,” Czech said.

North-Gran student Trinity Daniel said even without power, the building was still warm. However, the lights did not work and neither did the electronic toilets.

“The bathroom wasn’t working,” student Selena Daniel said. “You can’t flush the toilet and can’t use the sink, it’s ridiculous.

CPS expects all schools to have power by Tuesday.