Acting Essex County Prosecutor Carolyn A. Murray said Thursday that 34-year-old Nicole Dufault, of Caldwell, was arrested Wednesday night for the incidents that happened inside Columbia High School in Maplewood and in her car since last year.
She was being held on $500,000 bail at the Essex County Correctional Facility and police say they removed her two children from her custody.
It wasn't immediately clear if Dufault had an attorney.
Prosecutors say Dufault is a language arts teacher and has worked at the school for nine years.
The school was offering counseling and other assistance.