The Northern Tioga School District (NTSD) is a rural public school district operating in Tioga County, Pennsylvania, US. The district serves an extensive rural region, spanning 335 square miles (870 km2) across the northern section of Tioga County. Northern Tioga School District is a third class school district having less than 30,000 residents and is one of the 500 public school districts of Pennsylvania. Municipalities served include: Tioga, Tioga Township, Jackson Township, Lawrenceville, Lawrence Township, Farmington Township, Elkland, Osceola Township, Knoxville, Chatham Township, Deerfield Township, Brookfield, Westfield, and Clymer Township. According to 2000 federal census data, it served a resident population of 14,670. By 2010, the district's population declined to 14,523 people. The educational attainment levels for the Northern Tioga School District population were 85.6% high school graduates and 11.7% college graduates.