Complex sentence: It is the sole high school of the Mifflin County School District, serves 1,272 students in Grades 10-12 and was established in 2011, merging the district's two former high schools (Indian Valley and Lewistown Area).
Split into simpler sentences: It is the sole high school of the Mifflin County School District, serves 1,272 students in Grades 10-12. The school was established in 2011, merging the district's two former high schools (Indian Valley and Lewistown Area).