Strathroy District Collegiate Institute (SDCI) is one of two secondary schools in Strathroy, Ontario. It is a public high school in the Thames Valley District School Board. The school services feeder schools in the Strathroy area, as well as the outer regions such as Mt. Brydges, Parkhill, Kerwood, Coldstream, Poplar Hill, Glencoe and Delaware. A new facility was opened in the fall of 2002 in a unique shared building with the catholic school Holy Cross Catholic Secondary School. The two schools share some facilities, including the five gyms, the library, the cafeteria, the auditorium, computer labs, technology labs, and various other classrooms, while also maintaining completely separate schools. The school's academic achievements are well above average for EQAO math testing. SDCI's Principal is Bruce Nielsen.
On September 3, 2002 over a thousand students, staff and alumni walked with the director, Bill Bryce from the old school site at 96 Kittridge Street East some 3.2 kilometres to the new building at 361 Second Street. They walked behind a huge student made banner declaring that "SDCI LIVES ON".
SDCI has named three classrooms in honour of famous graduates. Two history classrooms, Room 249 and 247, have been named after Sir Arthur Currie and James T. Shotwell. The music room has been named after Don Wright. In addition, one English classroom, Room 232, is named after Stephen Leacock.
During the 2004-2005 school year, three portable classrooms were brought to SDCI. After two years of lobbying, Strathroy was granted an addition, completed in January 2008. Construction started on November 13, 2006 at two different sites. The north addition has 14 academic classrooms, and renovations were conducted in the existing building to accommodate SDCI's growing developmental program. The other addition includes a new gym, a greenhouse, and specialty rooms for hospitality and technology.