The Shelby County (Tenn.) school system is large—with 48,211 students, it ranked as the 98th-largest U.S. system in 2009-10. But within a couple of years, the school system will claim a place near the top of the list of the nation’s largest districts.

The county includes the city of Memphis, but until now, Memphis has operated its own school system, much larger than and separate from the surrounding county district. That is going to change. The two districts are to become one by the 2013-14 school year. The consolidation was set in motion by the Memphis school board, and after a federal judge rejected a legal challenge from the Shelby County board, the two districts agreed to a settlement that maps out a plan for creating one Shelby County district.

In 2009-10, Memphis ranked 22nd with 109,300 students, and Shelby County was the 98th-largest district with 48,211 students. If those districts had been combined for the 2009-10 school year, the system’s 157,511 students would have placed it just ahead of the Dallas school system as the nation’s 15th-largest district.

The historical trend of district unification and consolidation has created many of the nation’s largest school systems. The United States had 119,000 school districts in 1937-38, according to the National Center for Education Statistics. A half-century later, that number had plummeted to 15,577. By 2009-10, the count of regular school districts in the United States was 13,629.

In Tennessee, several of the state’s larger districts have been formed by the merger of city and county systems. Nashville and Davidson County districts merged in the early 1960s; Knoxville and Knox County districts combined in 1987-88; and Chattanooga and Hamilton County districts consolidated in 1997-98.

The most recent chapter in the effort to combine Memphis and Shelby County schools began in December 2010, when the Memphis board voted to surrender its charter to operate and transfer administration of its schools to the Shelby County board. Memphis residents voted overwhelmingly in March to support ending the city-only school system. However, the Shelby County board unanimously opposed absorbing Memphis schools into its system, and went to court to try to stop the consolidation.

U.S. District Court Judge Samuel "Hardy" Mays ruled in August that the Memphis board’s decision to turn over its schools to Shelby County was legally valid.

"The Memphis City Schools has been abolished for all purposes except the winding down of its operations and the transfer of administration to the Shelby County Board of Education," Mays wrote.

Shortly after the judge’s ruling, Memphis and Shelby County officials agreed on a settlement that spells out the transition to a consolidated school system. A 23-member board will take over Oct. 1. It will have the nine Memphis board members and the seven Shelby County board members now serving. Seven additional members will be appointed to represent seven new countywide districts. The seven appointed seats are up for election in August 2012; on Sept. 1, 2013, the 16 members from the previous boards will end terms, and the remaining seven members will govern the merged system.