When students return to Naperville Central High School after winter break, some new classrooms will be ready for use, as construction on the music department is now complete.

Along with ongoing construction projects at Naperville Central, the district is planning renovation projects over the summer at two elementary schools in the district.

Construction at Naperville Central is "on budget and on time," said Ralph Weaver, Naperville School District 203's director of facilities and construction.

The music department renovations have been completed, but more work needs to be done at the school, Weaver said. Work on the school's north addition, facing Aurora Avenue, is currently under construction and should be completed this spring, before the school year ends.

Renovations on the area known as the "flat wing" will be completed over the summer, Weaver said. The flat wing is adjacent to the band area, to the west of the administration area. Everything in that area will be reconstructed over the summer, said Terry Fielden, a school board member and a member of the board facilities sub-committee.

The changes will take place quickly, and the school will go from the 1960s to 2011 in 90 days, Fielden said. Even so, the schedule is not as aggressive as the construction was last summer, he said.

After encountering some problems with the school's heating and cooling system in 2010, the district took the step of hiring a commissioning agent, Fielden said. The agent reviews the system and makes sure it is functioning properly at top performance.

"It's an extra level of protection so when we take them over, we know they are functioning properly," Fielden said. "It's cheap insurance to hire an agent to oversee a building of more than 550,000 square feet. The district needs to have some comfort knowing it is working right."

Once the construction is complete at the school, very little of the original heating and cooling system will remain, he said.

Along with the summer construction at Naperville Central, two projects are expected to take place at Prairie and Ranch View elementary schools. They are two of the last of the referenda projects, Weaver said.

The projects at the elementary schools will provide better security at the main entrances, Fielden said.

"Laurie Dann really started the whole discussion about safety," he said, referring to the rampage in May 1988, during which Dann entered a school in Winnetka and killed a boy and injured other students befor fleeing and committing suicide.

At Prairie, the main office is tucked inside the center of the building, Fielden said. The district is planning to build a small addition that will allow for increased visibility of everyone entering and exiting the building.

At Ranch View, rather than constructing an addition, the best security option was deemed to be relocating several kindergarten classrooms and a music room, Fielden said. In addition to the improved safety, the changes will also allow for better natural light in the rooms and better views of the outside surroundings.

The projects will go out for bids early in the year and the work is expected to take place over the summer, Weaver said.

"When school opens in August, we should have them completed," Weaver said.