For several years the district had considered closing Southwestern. Robert Bobb, who served as the Detroit Public Schools emergency manager, had almost closed Southwestern. By February 2012 the school district announced that it had plans to close Southwestern at the end of the school year. Several protestors challenged the school closing proposal. Aaron Foley of MLive said that the protestors were concerned about a loss of bilingual education employees and fears of a rivalry with students at Western International High School. The school closed. It students were moved to Northwestern High School and Western International. The school's contents were made for sale over the internet in October 2012. DPS officials said that making the sale online would save $85,000 of school funds.
In 1926, Prospector trackman Kalman Bator won the Michigan High School Athletic Association title in the javelin throw. Seventy-four years later, William Agee became the first Southwestern student-athlete since Bator to win a MHSAA championship; Agee took first place in the 110-meter high hurdles, at the 2000 state finals.