The Mississippi teacher is now out of a job, according to a report by WTVA.
The former Calhoun City High School employee, who remains unnamed, allegedly mistook the treats for beef jerky.
District superintendent Dr Lisa Langford said that at least eight children took at least one bite of the dog treats.
Langford commended the school nurse for her swift response, which included calling Poison Control.
Parents were also notified about the situation.
WTVA also said at least one child was taken to the doctor for a stomachache.