The King's Academy in Seymour is the first school locally to close because of the flu this season.
School staff say about 15 percent of students were absent Monday, and many more left early because they were sick.
In some classes, 30 percent of the students were out.
Administrators at the school said they can only remember one other time in the last 30 years when they closed because of the flu, but with the sickness spreading quickly down the halls, they sent the kids away for a deep clean of the whole campus.
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Just two women roamed the halls Tuesday, tasked with putting an end to the flu virus plaguing The King's Academy. It would have been three, but the third custodian was home sick with the flu.
Armed with Clorox wipes, Lysol spray and disinfectant foggers, they started working Monday afternoon to disinfect the campus.
"We don't want to give it the two days and not try to do everything we can think of, so I think it's going to make a difference," middle and high school principal Rex Smith said.
He said 55 students were out of school Monday because they were sick.
For the small school of just over 400 kids, that's a pretty big dent.
"It was very difficult for the teachers to try to plan lessons," Smith said. "We have a lot of kids who are absent and so we just wanted to have a couple days to maybe clean the school very well and let people recover."
They also struggled to find enough substitute teachers to fill in for their sick staff members.
As far as other school districts go, Knox County Schools reported 92 percent of its students were in school Tuesday, which is reportedly average.
Blount County reported the same numbers, but said when attendance drops to 90 percent, "the district begins considering additional preventative measures," said Blount County Schools Communication Director Marla Holbert.
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Anderson County Schools is starting to worry the flu is spreading there. The district's attendance rate dropped 5 percent from Monday to Tuesday, alarming school officials. But the district has not canceled class.
Smith said he's glad The King's Academy closed when it did.
"A lot of parents, I think, were just getting afraid to send their kid to school, and that's understandable," Smith said. "So I think those parents of even the healthy kids are OK that we're going to take a couple days off."
The King's Academy will resume classes on Thursday.