The original building was destroyed by one of the worst tornadoes in Illinois history. The
Plainfield Tornado, which was rated an
F5, struck the town on August 28, 1990, one day before classes were scheduled to begin. Three faculty and staff members lost their lives during this storm. Had school been in session, casualties could have been even more grave, as the tornado hit the school directly. In the middle of the 1992–1993 school year students moved into the new PHS building. At the time, it was one of the most technically advanced high schools in the state of Illinois, complete with its own observatory. In 1998, the school added a "Freshman Center" with its own
gymnasium and
cafeteria. The new freshman center has three floors and is connected to the main building by an enclosed
catwalk. At the start of the 2024-2025 school year, it was renamed the "North Building". In 2005, the school constructed a new snack building and restrooms on the south end of the football–track
stadium. In 2007, a new home
grandstand was constructed, replacing the visitors' seating on the west side of the football field, and the former home grandstand was converted into visitor seating. The new home grandstand was built using only steel, contrasting with the former home seating which was constructed of
brick and
concrete. The grandstand opening had been planned for the pre-season 'Green and White Night' event, but construction set-backs led to its opening about one month late. With the addition of a larger home grandstand,
shot put and
discus fields were relocated further west, behind the new grandstand. Also in 2007, the faculty installed over 300
high-resolution wireless cameras to monitor the campus. New computer security measures were implemented which
block some
internet proxy servers, game-related sites, and other sites that the school district felt distracted their students from the educational process. The school replaced all its computers and monitors with
Dell computers with
LCD screens. In the 2008-2009 school year, classroom projectors that could display what was on the current teacher's computer were installed. On June 9, 2008,
severe weather resulted in damage to the tennis court fences and school roof. Although this occurred during a
prolonged tornado outbreak throughout the United States, there were no confirmed reports of a tornado. ==Athletics & Activities==