Spring and Klein ISDs comprise an area of unincorporated Harris County, which includes nine ZIP codes* and more than 350,000 people. Most of the communities served by these districts are located between Hwy. 249 and I-45, FM 1960 and Grand Parkway. *ZIP codes 77066, 77068, 77069, 77070, 77090, 77373, 77379, 77388, 77389