Chinle Unified School District  Chinle Unified School District No. 24 (CUSD) is a school district headquartered in Chinle, a census-designated place in Apache County, Arizona, United States. CUSD serves several unincorporated areas in Apache County, including Chinle, Del Muerto, Lukachukai, Many Farms, Nazlini, Rough Rock, Sehili, Tsaile, and small portions of Round Rock and Sawmill. The areas the school serves are within the Navajo Nation. In July 1983 the Red Mesa Unified School District formed, splitting from the Chinle School District. Chinle Unified School District celebrated its 50th anniversary in 2008. A district orientation at the Wildcat Den on July 25, 2008 celebrated this milestone event.   the district had about 3,600 students, with about 99% of them being Navajo people, a.k.a. Diné. In 1998 there were more than 4,500 students, with 95% of them being Navajo. The following left when the Red Mesa Unified School District formed: