It was built in 1909 and has had many major renovations over its 110 year lifespan, including the addition of an indoor swimming pool, two gymnasiums, auditorium, cafeteria, library, and 100+ more classrooms.

In 2015, The Football field grass was replaced with Artificial turf, The track and tennis courts were both redone East Campus received another Major Renovation in 2017 which added a new atrium, 4 New Science Labs, A New Kitchen, A Pre-School Classroom with Observation Area, and 10 New Classrooms.

The three-story building was built of local dolomitic limestone, with a four-sided clock tower on its roof.

With these additions, the high school now occupies the entire block of Twelfth, Jefferson, Thirteenth, and Madison Streets.

By 2009, district officials have been grappling with an influx of 1,200 students in 10 years,[8] since Central and East Campuses both presently operate over their design capacities.

Major issues of contention in the voting continue to include the proposed boundary line designating the areas to be serviced by each high school, and concerns that Homer Glen voters might try to break from the district and either form a new high school district or join with Homer Glen Elementary district 33-C. Homer Glen already has bought the land that the new high school would be built on and is waiting on the people of Lockport to stop voting down the referendum.

[10] In the sixth referendum, in April 2011, a proposal for an $85 million bond issue for the new school lost by about 1,300 votes.

Lockport competes in the Southwest Suburban Conference and is a member of the Illinois High School Association (IHSA), the body which governs most sports and competitive activities in the state.

The school sponsors interscholastic teams for young men and women in badminton, baseball, basketball, bowling, cheerleading, cross country, dance team, football, golf, soccer, softball, swimming, tennis, track, volleyball, and wrestling.

The following teams have won or placed in the top four of their respective state championship competitions sponsored by the IHSA: