(NewsNation) — The number of students and teachers who miss at least 18 days of the school year has grown at an alarming rate since the COVID-19 pandemic but is becoming more problematic thanks to a ripple effect that disrupts the classroom culture across the country.

When 10% of a student’s classmates are absent on one day, that student is nearly 20% more likely to be absent the following day, a Texas Tech University study found.

While the U.S. Department of Education targeted chronic absenteeism (defined as students who miss at least 10% of the school year) as being problematic in 2016 when an estimated 7 million kids fell into that category, the issue has only worsened.

The 15% of public school students considered chronically absent in 2018 jumped to 28% in 2022, a study conducted by the American Enterprise Institute shows.  At the same time, data shows that 72% of U.S. public schools reported teachers missed more classroom time than they did before 2020.

Experts say that while those who miss school the most can fall along racial and socioeconomic lines, the fact districts across the board have seen nearly 50% increases makes absenteeism the top issue facing public education today.

“The good thing is that it wasn’t that long ago that more people went to school much more regularly,” Nat Malkus, senior fellow and deputy director of education policy studies at AEI, told NewsNation. “So, we can get back there. But if we don’t do it quickly, we’re in real danger that this could be the new normal. And that would be bad.”

Kids skipping school stick together

While studies show students who miss in-person learning often struggle to keep their grades up and graduate, they also tend to suffer in social and emotional ways because they lose engagement with their peers and other members of their school community.

That can be blamed on the nation’s relationship with education becoming “optional”, Katie Rosanbalm, a psychologist and associate research professor with the Center for Child and Family Policy at Duke University, told the New York Times.

Turan Crockett, the principal at Wendell Smith Elementary in Chicago’s Pullman neighborhood, has seen that first-hand, even at a school that had an attendance rate of 84% coming out of the pandemic.

Crockett said students who are allowed to sleep over at a classmate’s house can become packs of students who do not show up for school.

“If (a student) misses two weeks of school, we have to re-set, we have to re-form relationships, we have to re-set the classroom expectations and we have to circle back on things that students are already accustomed to,” Crockett told NewsNation.

Classroom disruption has been seen the most in Alaska, New Mexico, and The District of Columbia, where more than 40% of students missed at least 10% of the school year in 2021-22, according to data from Attendance Works, which tracks school attendance. New Mexico showed the biggest jump, going from 17.9% in 2018 to 40.4% in 2022.

Holding teachers accountable

While the majority of the attention has remained on absent students, teachers have also demonstrated habits of spending more time away from the pandemic, data shows. Those absences are traditionally built around scheduled days off or school breaks when experts say that more teachers are calling in sick, creating even more disruption in the learning process for students.

“When this level of churn in the classroom exists, it makes it harder for teachers to teach since they have to repeat lessons and set classroom norms,” Hedy Nai-Lin Chang, Attendance Works’ executive director and president told NewsNation.

In Rhode Island, education officials cracked down on teacher attendance after four Pawtucket schools reported chronic absenteeism rates higher than 40% of teachers who missed at least 18 days on the job in a given school year.

Crockett, the Chicago principal, says that stressing in-person attendance for teachers is now part of the back-to-school training sessions.

Hybrid mindset adds to the problem

Malkus says that the habit of regular school attendance became broken by the pandemic. It was made worse by employers making in-person work an option rather than a requirement, he said.

It’s created more heavy lifting for educators, who are now forced to reshape attendance habits and proper mindsets about the importance of in-person schooling.

“It’s a huge concern knowing that people at large are reverting to the hybrid model or the virtual model as an option when it should always be in person,” Crockett said.

Between illness, transportation issues, and a student’s aversion to the school environment, Attendance Now experts found absenteeism can still be linked to common excuses in most instances, along with the ongoing skepticism among parents that schools are safe.

Experts believe that communication between the school, students and their parents remains the key to tackling chronic absenteeism. But time is of the utmost importance, Malkus said.

While the first year coming out of any trend typically boasts the largest bounce-back effect, the 2022-23 school year only showed a 2 percentage point improvement in school attendance from the prior year.

Nationally, schools remain 13 percentage points behind where they were as a whole in 2018, meaning that if improvement continues to grow at the same rate as it did last year, at least another six years will pass before school attendance is back on track.

“It’s going to take all-hands-on-deck and paying attention (to the issue) week in and week out to get back to the routines that weren’t atypical just five years ago,” Malkus said.