Jayvone Johnson, 34, who was arrested in December, pleaded not guilty to the crime, sources said.
Johnson was a coach at the Icahn Charter School 2 in Morris Park, sources said.
The school said it takes students safety very seriously and is cooperating with authorities.
A spokesperson said that Johnson no longer works at the school.
Police are asking any potential victims to come forward by calling Crime Stoppers at 1-800-577-TIPS.
Johnson was given supervised released and is expected back in court on Feb. 11.