"One day a few weeks ago, one of the assistants was going through a filing cabinet and found a file that had a manuscript from The Breakfast Club dated Sept. 21, 1983," District superintendent of Maine Township High School District 207 Ken Wallace told the Chicago Tribune. "It's a first draft of the screenplay by John Hughes."
The manuscript didn't just appear there, however. The cult classic was filmed inside the high school during the spring of 1984. The school's indoor gym served as the sound stage for the famous 1985 movie's library set.