At McKinley Elementary School in Fairfield, Conn., school's out -- not just for summer, but maybe for good, reports CBS News Correspondent Jim Axelrod.
When a number of teachers and kids reported a rash of unexplained symptoms, local allergist Dr. John Santilli, put two and two together. He had testing done for mold in the school.
"They found the typical indoor molds aspergillus, penicillium. But what they found that was significant was stachibotrys," said Santilli. "Once we started getting the testing results back it became obvious that McKinley was not a problem, but a huge problem."
Santilli estimates some 40 to 60 students and staff got sick from the mold. Two cases were serious enough to require hospitalization.
According to town selectmen Ken Flatto, the problem started with some late summer flooding.
"When I went in to clean out materials in a closet, the materials had black mold all over them," said Joellen Lawson.
That cleanup took the 23-year teaching veteran out of the classroom and into the hospital, under the care of Santilli.
"He said my symptoms -- the respiratory symptoms, the neurological, the sensory disturbances that I have been suffering for years were totally consistent with exposure to high levels of mold," she said.
Santilli says he has a dozen kids and teachers homebound. "I won't let them go back to school."
Stories like Lawson's become even more alarming when one realizes some 14 million American children attend schools with poor environmental conditions. In the last decade the rate of allergic disease -- like asthma -- has doubled in the nation's classrooms. Many say that's also the place to look for the cause.
In Portland, Ore., parents started asking questions when students and teachers at Whitaker Middle School started complaining of fatigue, head aches and flu-like symptoms.
Said teacher Janis Ingersole, "I felt like something was standing on my chest. My skin was crawling. I had hives and my face was puffed up like a pink."
When the school was tested, what was first thought to be radon turned out to be mold. Leaks from an old, poorly maintained, drainage system caused flooding. The flooding spawned mold.
"How many more teachers have to get sick before people realize this is a serious public issue?" asks Lawson. She is now pushing Connecticut legislators to enact new air quality standards in state classrooms.
"Children should not have to attend school where they are going to acquire a life-long illness."
Joellen Lawson is making the dangers of mold her last lesson -- now that it's left her unable to teach anything else.