Teresa Gilmete Badger of Matthew Turner Elementary School in Benicia, Calif., allegedly brought the marijuana-laced food to an after-hours gathering in November.
Several people reported feeling ill after the potluck and a 15-year-old also got sick from leftovers that one attendee brought home.
Badger was arrested on the felony charge of suspicion of willfully mingling a poison or harmful substance with food following a six-week investigation.
"One of the partygoers was rushed to the hospital with severe reactions; she was hospitalized," said Lt. Frank Hartig. "The very next morning, another partygoer was taken to the hospital, because she continued to feel like she was under the influence of something."
Tests on one of the victims revealed the presence of THC, one of the primary chemicals in marijuana.
The 47-year-old teacher is being held at the Solano County Jail in Fairfield.
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