The school has been closed to students since Thursday, when a pesticide odor sickened 13 students and two teachers.

School officials will use the additional day for final cleaning and to make sure the school is safe and ready when students and teachers return Thursday, the Department of Education said in a press release.

The Department of Health has conducted tests and declared the campus to be free of contaminants. However, some adults continued to express mild discomfort, primarily throat constriction, in the affected upper part of the campus this morning.

The Department of Agriculture initiated an investigation Friday and was looking into whether the odor came from a turf farmer nearby who was testing a pesticide on his crop.

Samples were taken to determine if residue in the classrooms is the same as the pesticide, but the results won't be known for two to three weeks, Robert Boesch, the Agriculture Department's pesticide program manager, said yesterday.

Boesch said the farmer had stated that he was using the pesticide for the first time, because of a problem with aphids.

When he was at the school Friday, Boesch said he was unable to detect the chemical odor in the classroom that the school said was most affected.

"It was more of a moldy, musty smell," he said, whereas the smell from the chemical was more "sweet."