The Santa Fe New Mexican reports that the Gonzales Community School teacher told investigators that she wasn't trying to harm the boy.
Police Sgt. Andrea Dobyns says the act was still negligent.
Dobyns says the boy complained to a school nurse that his head hurt afterward but he required no medical attention.
The incident occurred Nov. 15, and police were notified a week later by school staff.
The family didn't want to press charges.
Police didn't identify the teacher because she hasn't been criminally charged.