Cotterell's attorney says Cotterell has psychological issues and is receiving professional treatment.
Her attorney says they decided against going to trial to avoid resurrecting other unrelated violent and traumatic incidents in Cotterell's past.
The judge concurred and allowed Cotterell to be released immediately after official booking.
Rio School District School Board President Tim Blaylock says Cotterell's plea will not affect her job, and she has the full support of the school board.
The Associated Press contributed to this report.