Complex sentence: Barnegat Township has completed its withdrawal from the Southern Regional School District, and by the 2007-08 school year has had ninth through twelfth grades attending the new Barnegat High School, which built its own high school in lieu of being a sending district.
Split into simpler sentences: Barnegat Township has completed its withdrawal from the Southern Regional School District, and for the 2007-08 school year has ninth through twelfth grades attending the new Barnegat High School. Barnegat has built its own high school in lieu of being a sending district.