Klein Inependent School District (Klein ISD) is a school district that covers 87.5 square miles of land in Harris County, Texas, United States. Almost all of the territory is unincorporated; a small portion of Houston is within the district's limits. 41,800 students attend Klein ISD Schools for the 2007-08 school year. Klein ISD is part of the taxation base for Lone Star College System. Dr. Jim Cain is Superintendent of Schools.