Klein Independent School District (Klein ISD) is a school district that covers 87.5 square miles (227 km2) in Harris County, Texas, United States. It became an independent school district in 1938. Almost all of the territory is unincorporated; a small portion of Houston is within the district. In the 2020–2021 school year, Klein ISD had 52,824 students. Klein ISD is part of the taxation base for the Lone Star College System. As of 2022, Jenny McGown is Superintendent of Schools.