By 1950, enrollment was growing significantly each year, so much so that ninth graders were being educated in a separate building at West 43rd Street and Wentworth Avenue in south Minneapolis. The school's administration opened a new residence for the Christian Brothers in 1950, facing Grove Street on the back side of the DeLaSalle campus. In 1960, in order to "bring the freshmen back to the Island," the school opened the third classroom building on campus (today known as the "A building"). The original school building stood until February 1971, when a weekend electrical fire damaged much of the structure. Because enrollment was dropping precipitously at the time, the original building was razed and not replaced.