Cassia County Joint School District 151 is the 13th largest district in the state, in terms of student enrollment. The district encompasses most of Cassia County plus small portions of Oneida and Twin Falls Counties and is geographically larger than the state of Delaware. Within these 2,500 square miles are 18 schools with a total enrollment of 5,600 students. All schools are on a semester schedule and are accredited through the Northwest Accreditation Association and/or the State Department of Education. The district employs certified staff of over 340, 1/3 of whom have advanced degrees. Ancillary and auxiliary personnel bring the total number of employees to about 800 making the district the largest employer in the county.

Cassia became a countywide consolidated district in 1948. Prior to that there were 49 school districts spread throughout Cassia County. By merging into a consolidated district, they gained efficiencies and access to educational and financial resources. The schools of Cassia County continue to provide exceptional educational and extra curricular activites. Students, teams, and faculty are regularly awarded state and national honors and recognition.

 School sessions begin in late August. Dates of registration are announced each fall through the local news media. Preliminary registration for high school and junior high students are held in the spring when possible.