As the pandemic continues to race across the United States, many cities postponed or completely suspended plans to hold classes in person. But in many cases some students did not show up for school at all. In Tampa Florida, school social worker Laura Tucker who works in Hillsborough County, one of the state’s largest school districts told CBS the drop in enrollment has been unprecedented.

“I’ll try anything to find students who need to be in school. But this is uncharted ground,” she said. “We’ve never had to look this hard– for kids, in my career.”

Working from her SUV, Tucker is one of 235 social workers in the Hillsborough County School District. She told the network that she and her colleagues have been tasked with finding these children. Many of whom simply did not enroll. And it is not just a case of not having computer equipment to log in online—many students have lost their homes and are face with homelessness and other issues.

“I don’t know if it’s paperwork,” she told CBS. “I think a portion of them– moved away. I think a portion of them are doing their own thing. They’re homeschooling and they just haven’t notified our homeschool office that that’s what they’ve decided to do. And then some of them just aren’t doing school.”

“No one is keeping track of how many kids nationwide are not in school because of the pandemic,” CBS’ 60 minutes reports. So, it “compiled enrollment data from 78 of the largest school districts in the country. The results were alarming – districts reported that when school started, at least 240,000 students were unaccounted for.”

You can learn more in this 60 Minutes special report.