Inside the wall of tinted windows light showed students streaming to and from class.
Above them on the roof more than a thousand solar panels were converting light into electric power.
On Wednesday, at a ceremony outside those windows and some 50 feet below the roof, speaker after speaker spoke of the connection between the students in the building and the panels on the roof.
For one, said Swampscott Superintendent Lynne Celli, the panels on two Swampscott schools will generate about 19 percent of the district's energy needs at a fixed price for 20 years.
Constellation Energy of Baltimore, Md., installed, owns and will maintain the systems. In return, the town will purchase and receive all of the electricity generated by the solar panels under that 20-year agreement, according to Constellation.
Meanwhile, Swampscott students can monitor data on the energy and clean air the panels produce by reading digital screens mounted in school hallways.
Eventually they will acces the data as part of their science and technology curriculum.
Swampscott High seniors Kathy Vu and Ashley Zogba were the ceremonial ribbon cutters Wednesday celebrating the completion of the 450-kilowatt solar generation project at Swampscott Middle School and Swampscott High School.
In the mid-morning sun the students said that they are learning in their environmental science class how solar and wind power can produce energy for not just schools but Swampscott homes and businesses.
Kathy plans to attend Virginia Commonwealth next year and study the sciences.
Ashley plans to attend William Paterson University with an interest in law.
Michael Smith, a Constellation Energy executive, said the world is on the cusp of a revolution in the production and use of renewable energy.
A solar project at a school informs and inspires young people to learn about alternative energy and, perhaps, become part of the technical innovations afoot.
"This is about changing the future for our kids," he said.
Students are already involved.
Two students among the 60 or so people in the crowd Wednesday, Kyle Rogers and Jared Gardinas, have been going around to classrooms in the school each week for the past two years collecting recyclables including paper and cardboard.
They ferry the load to a Dumpster for materials that are recycled.
They feel good about the service because it benefits everyone.
"The big thing is that people can take this," said Jared, pointing to a bottle of vitamin water he was holding, "and reuse it."
Speaker Rich Malagrifa, the chairman of the Swampscott Board of Selectmen, said the town is exploring more and more ways to reduce energy costs.
"So, we are not stopping here," he said. "We are moving ahead with cost savings and renewable energy in Swampscott."