At Camden Hills Regional High School, an interdisciplinary education can mean mixing history with literature or science with philosophy; it can also mean building a castle. Student members of the school’s backstage tech team are doing just that as preparations move forward for “Once Upon a Mattress,” this year’s musical, opening Friday, Nov. 5.

Engineering, mathematics, physics, economics, and computer skills all came into play when CHRHS senior Alexander (“Domingo”) Sunde-Brown designed the six-foot-wide staircase that will wrap one of the set’s two castle turrets. The castle itself was designed by Vanessa Bemis, also a senior, who drew on her background in painting and sculpture and her love for literature to fashion a fortress both whimsical and medieval. The musical, made famous by Carol Burnett in the 1950s and ’60s, is based on Hans Christian Andersen’s “The Princess and the Pea.”

Working with fellow crew members as well as students enrolled in tech director Rick Ash’s Technical Theater courses, Sunde-Brown and Bemis knew their set had to be as safe as it is impressive. They also had to work within a budget.

“Each step of the staircase is cross-braced with extra strapping, and all the potentially weak points are reinforced,” said Sunde-Brown. “I had to revise my sketch three times on the computer before I got it just right and figured out how to get three steps out of each sheet of plywood.”

Another challenge was the design of the 20 mattresses around which the plot revolves. If the team used actual mattresses, there would be a weight problem: they would be too heavy to stack. The solution turned out to be facades created from batting, fabric and plywood strips.

“We’re using many different textiles to cover the facades,” Bemis said. “When we’re finished they’ll look a lot like real mattresses.”

Designing and constructing the complex set has required dedication and physical effort, with students working after school most days, and Saturdays too. But the team has had a couple of advantages. For one thing, this is the second castle the school has built, said Sunde-Brown, who hopes to becomes a math teacher one day. The first was for “Beauty and the Beast,” the fall musical when she and Bemis were sophomores.

Bemis, whose future plans include a possible career in publishing, said they have put a lot of time into making sure the “Mattress castle” is quite different from the Beast castle. The colors are more vivid, and the team is using plenty of brightly patterned fabrics to create the mattresses as well as the many flags and pennants that will decorate the castle.

Sunde-Brown is quick to point out a second advantage.

“Mr. Ash is always there for us. He keeps us focused and is ready with a suggestion when we need it. If we have a question, he guides us toward the answer. In the end, we figure it out for ourselves,” he said.

“Once Upon a Mattress” will run for five performances: Fridays and Saturdays, Nov. 5, 6, 12 and 13,  at 7 p.m.; and Sunday, Nov. 7 at 2 p.m. For tickets — $10 reserved, $6 and $8 general admission — call the CHRHS box office at 236-7800, ext. 282.

VillageSoup Art/Entertainment Editor Dagney Ernest can be reached at 207-594-4401 or by e-mail to dernest@villagesoup.com.