SUNBURY – A former substitute teacher at Shamokin Area School District pleaded guilty Wednesday morning to a felony count of unlawful contact with a minor and a misdemeanor of corruption of minors, and will be sentenced within 90 days.

Michael S. Zack, 24, of 201 Warsaw St., Marion Heights, entered his plea before President Judge Robert B. Sacavage after having been accused in March of sending approximately 4,300 text messages to two 17-year-old females and two 16-year-old girls who attended Shamokin Area at the time. Many of the messages, which were sent between March 15 and Oct. 30, 2011, depicted sexually graphic material, police said.

First Assistant District Attorney Ann Targonski said the standard range sentence for the felony count is three to 12 months in county prison, and that would involve intermediate punishment that would include at least 90 days of house arrest. The misdemeanor charge would involve a sentence of five years of probation, consecutive to the felony sentencing.

Prior to his plea, Zack also voluntarily signed an affidavit surrendering his teacher’s license, which had been suspended, Targonski said.

Zack was hired as a 180-day substitute teacher in the district in August 2011 and terminated by the school board at its December 2011 meeting, retroactive to Nov. 16, 2011.