The Kansas State High School Activities Association has moved SM South from the 6A classification to 5A for the 2012-2013 season based on enrollment figures collected September 20. SM South will continue to compete in 6A football this year as well as next year. KSHSAA uses the class system to ensure fair match-ups between schools, and the classes are determined by enrollment in grades 9-12.
For 2012-2013 the 6A class includes all schools with 1,336 to 2,276 students. The rest of the Shawnee Mission School District high schools fall into this category. The 5A class which now includes SM South is schools with 734 to 1,333 students. The anticipated enrollment at SM South for the 2013-2014 school year is 1,325.
You can find the rest of the school classifications here.