The school has undergone many changes over the century. It was built in 1929 as Harlingen High School. The school later became a Freshman only campus. When the Freshmen joined high school, Vernon housed only eighth graders. At the beginning of this decade, Vernon became one of three junior highs in Harlingen; all of these educated seventh and eighth grade students. In 1997 another change came to Vernon. Sixth grade students have become a part of secondary schools. The 1997-1998 sixth, seventh and eighth grade students were the first to attend Vernon Middle School.