They missed sitting in class, meeting their teachers, hanging out with friends, and walking the noisy hallways.

For 15 months, they learned remotely after the coronavirus abruptly shut down schools. Some districts didn’t fully reopen for the 2020-2021 school year or students decided not to return midyear.

“It has been extremely hard,” said Takayla Williams, 16, a junior at the Camden Big Picture Learning Academy. “I honestly feel like I didn’t learn anything.”

She was one of more than 1,400 high school students who spent the year in remote learning in Camden, one of the last South Jersey districts to reopen its schools. The district, which enrolls about 6,800 students, began returning its kindergarten through eighth graders in April.

Superintendent Katrina McCombs said she made the difficult decision to keep high schools closed after only about 25% of students said they would come back to the classroom. There were also health concerns about aging buildings that need repairs, she said. “I wanted them all back,” McCombs said.

The Philadelphia School District also had a fully remote year for its more than 25,000 students in grades 10 through 12. The Southeast Delco District, which enrolls 4,200 students in six schools, was the only school system in Delaware County that remained virtual for the entire year.

Across the region and country, many public schools reopened in September with hybrid learning models, where students attended traditional and online classes. Some parents and teachers opted for remote learning because of health and safety concerns. As the coronavirus infection rate declined and vaccination became available to teenagers and students 12 and older, school officials were more inclined to extend school reopenings.

» READ MORE: Schools open: Camden’s youngest students begin first day of in-person classes

Lenape Regional High School sophomore Nolan Samson, 16, returned to school June 2 for the last two weeks of the school year. He said he was getting bored at home and missed his friends.

“I had to go back at some point,” he said with a smile.

Gov. Phil Murphy has said New Jersey public schools must fully reopen in September and that districts will not be permitted to offer remote options. Philadelphia will offer virtual learning for families that want it.

The year was also tough on teachers, said Karen Borrelli, a longtime health and physical education teacher at Charles Brimm Medical Arts High School in Camden. She never saw some of her 100 freshmen and seniors who kept their cameras turned off.

“It really challenged me as an educator to figure out how to reach a TV screen,” Borrelli said.

Lewis Echevarria, 18, a junior at the Creative Arts Morgan Village Academy in Camden, was hopeful the shutdown would be short. An aspiring lawyer, he had an A average before the pandemic and saw his grades drop slightly in honors biology and history.

“I said it’s just 2 weeks. What’s the worst that can happen?” he recalled.

Echevarria logged into class from home, on his cell phone until he obtained a laptop from the district. His internet connection was often spotty. He missed school performances. Despite the obstacles, Echevarria believes he will be prepared for his upcoming senior year.

McCombs said about 30% of Camden’s high school students are lagging academically. Like many districts across the region, Camden is offering summer school to make up for learning loss. Juniors and seniors can take up to four courses. “We know that there is a lot of work we are going to need to do,” McCombs said.

For Camden High senior Zinasia Jackson, 18, the best part of the school year was attending the prom. Her class rank fell from No. 2 to 5, which she attributes to her struggles with remote learning. After graduation, she plans to enlist in the U.S. Navy.

“The whole senior year was taken from us,” Jackson said, adding that “it was the best that could have happened over the circumstances.”

Xavier Alexander, 17, a senior at Williamstown High School in Monroe Township in Gloucester County, said he had gotten into a routine with virtual learning and it made sense to stick with it.

“I was already in the groove remotely,” Alexander said.

Alexander will see his classmates in person for the second time at graduation on Friday (prom was the first time). Although he feels like he missed some key aspects of senior year, he’s ready for the next step — attending Howard University in the fall.

» READ MORE: Just because schools reopen doesn’t mean the kids show up

“It was definitely bittersweet,” he said. “But at the same time, it’s time to move on and accomplish new goals.”

Staff writers Kristen A. Graham and Maddie Hanna contributed to this article.