LPHS serves the communities and surrounding areas of LaSalle, Peru, Oglesby, Tonica, and Dimmick.

The high school takes students from the following townships: Dimmick, Waltham, Peru, LaSalle, Utica, Deer Park, Eden, Vermillion, Hope, and Richland.

LaSalle-Peru Township High School was built in 1897–98, occupying buildings on 5th, 6th and Chartres Streets in LaSalle.

There have been many additions throughout the years at L-P High School, including the West Gymnasium, Area Career Center and Dolan Building.

He was trying to coordinate the visit of a Big Ten school, and the university had African American members, and the director accommodated them accordingly.

[3] On the 2010 Prairie State Achievement Exam, 49% of L-P High School 11th graders met or exceeded standards in Reading.

As of 2010, the ethnic makeup of L-P High School was 85.7% White, 11.4% Hispanic, 2% Black, 0.9% Asian, and 0.2% Native American.

The Lasalle-Peru Color Guard adds the greatest visual to the band, whilst including rifle, flag, and backgrounds on wheels.

Jeremy Stevens, a former member of The Cavaliers Drum and Bugle Corps, is the current band director at LaSalle-Peru Township High School.