When science teacher Elisabeth Jellison returned to Vashon High School last week after two months away, she arrived to a much different scene than the one she left in June.

The school grounds are now a construction zone, complete with chain-link fences and heavy machinery. Large, gray portable classrooms have been set up on the south end of campus to hold science classes over the coming months, and in one area a long, metal tunnel has been put in place to protect students from flying debris as they walk to class.

Jellison and two other science teachers are now scrambling to prepare their classrooms for students to arrive in a week — not only unpacking their materials, but deciding how to alter their curriculum and labs for the smaller classroom space.

“I think it’s going to be a lot of work for us to get done, but we’ll get it done,” she said. “We’re those kind of people.”

Jellison and her colleagues aren’t the only teachers scrambling right now. None of the high school staff had access to the building over the summer while construction work consumed the campus. And at Chautauqua Elementary School, professional movers who were brought in last week helped teachers reassemble their classrooms after everything had been packed away so that smaller-scale construction work could be done over the summer there as well.

School district officials last week said some teachers and staff were hustling, but they were also sure both schools would be ready for students to arrive on Tuesday, the first day of classes across the district.

“I’m totally confident,” said Chautauqua principal Jodie Metzger last week. “The spirit has been really good.”

At VHS, principal Susan Hanson called the science department’s transition into portables “daunting” but said high school staff didn’t seem to mind being blocked from their classrooms this summer. Some teachers worked from home, she said, while others simply took the summer months off.

“Everybody else is business as usual,” she said. “No one has complained. I think we’re so excited about the beginning of our new building, and we understand things are going to be a little bit different.”

Hanson said she recently climbed to the top of the high school bleachers to survey the construction work in progress.

“It’s like watching a mechanized ballet,” she said.

To the untrained eye, it might look like crews hadn’t made much progress at the high school campus over the summer, said Eric Gill, the school district’s capital projects manager. During a tour of the construction site last week, Gill pointed out that no foundations or walls have gone up yet. The middle of campus is filled with dirt and gravel.

“People might come and say, ‘What have you been doing all summer? It looks like a field of dirt,’” he said.

But in fact, Gill said, crews have been working in overdrive the past three months, replacing and installing underground utilities while confronting a bevy of unexpected construction snags. The project is considered on schedule, he added.

“They’ve basically pulled off a miracle,” he said.

Spencer Blixt, project manager at the site and the father of a VHS graduate, agreed. He said once workers began to unearth utilities to install or upgrade water, electric, septic and other systems, many utility lines at the decades-old site were not where the district expected them to be.

“When you get into a site that’s 80 years old, there are always some unknowns you deal with,” said Blixt as he stood next to a big diagram of the construction plans. “This one — it was full of unknowns.”

Gill said the tightly intertwined utility lines — some to be replaced this summer and others to be left to feed the existing high school for the next year and a half — posed a challenge for the construction team. The surprises meant plans often had to be adjusted on the fly.

“It’s a 3D puzzle,” he said. “It’s all got to come together.”

But the team pushed hard, Blixt said, and it looks like the campus will be ready to partially reopen just in time for staff and students to return.

“The date was not moveable,” he said. “We could now allow that to fail.”

At Chautauqua, teachers returned to a different situation — a building that on the outside looked much the same but not so on the inside. Hallways and classrooms were flooded with furniture and boxes — a sign that construction crews have been busy at the elementary school as well.

Over the summer, Chautauqua classrooms were packed away so crews could install hookups for faster Internet service, part of a district-wide technology upgrade. The school’s heating and ventilation system was also refurbished, requiring work in each room.

In addition, the school district offices moved from their temporary home in classrooms on the bottom floor of Chautauqua to newly built offices on the building’s top floor.

The bottom floor space was converted back to classrooms, and in the process about 10 classes changed location. “There was lots of shuffling,” Metzger said.

On Friday, first-grade teacher Holly Boyajian seemed frantic as she rushed around Chautauqua making preparations for the new year. She said she spent some time over the summer preparing lesson plans at home while also working on earning her master’s degree. But she still had a lot of work ahead to prepare her classroom, she said.

Despite the rush, she said she was excited about the new year and had no complaints about the district’s process.

“All of this was for a good purpose,” she said.

Glenda Berliner, a multi-age teacher who stopped to talk with Boyajian, seemed calm as she arranged books in her own classroom. Berliner, one of the teachers moving into a new room, said she was actually glad to have no access to her classroom over the summer. She took some needed time off, she said. “It was a blessing,” she said with a chuckle.

Though her classroom was in disarray, furniture scattered and materials all packed in boxes, Berliner was confident she would have enough time to get everything arranged.

“It’s always a little tight,” she said.

Chautauqua’s closure was a challenge for some teachers who would normally spend time in their classrooms during the summer months, and it will definitely be a push to open Sept. 4, but spirits have been high, Metzger said.

Some will likely work through the weekend to ready their classes, she added, while others might greet students with rooms not fully decorated and wait for student work to adorn the walls.

“It’s really for the children,” she said. “It’s doesn’t have to be Martha Stewart.”