Officials were notified after a 7th grade teacher noticed some of the students were sleepy and acting "not quite right."
After asking what was going on, that teacher learned a 13-year-old took prescription pills and passed them out to others students.
Those students then began to feel sick.
A total of seven students involved were taken to St. Christopher's Hospital for Children for evaluation.
One of the girls who took the pills, Onia Cortez, spoke to Action News with her parents' permission.
"I thought it was candy or something. I just took it back and started chewing," she said. "It was my mistake, I understand."
The girls took Ambien sleeping pills, according to the school district. Parents were notified by letters that went home with students explaining what happened.
Two girls were admitted to the hospital. Their parents told Action News they believe the girls took more than just Ambien.
"She's sick, her heart rate keeps going up and down, she passed out," said Marisol Cruz.
"Heart rate keeps going up and down, up and down. They haven't been able to stabilize the girls' heart rate at all due to the side effects of the pills," said Sylvia Vasquez.
The 13-year-old girl is now in police custody. She will likely face charges and be suspended from school.