David and Mary Thomson Collegiate Institute is an English-language high school located in Scarborough, Toronto, Ontario, Canada. David and Mary Thomson C.I. was opened in September, 1959. This school is located in the heart of historical Scarborough. It was named after Scarborough's first European pioneers, David and Mary Thomson. The land David and Mary Thomson C.I. is located on was owned by descendants of the Thomson family.
The Thomson Music Department offers a comprehensive band and vocal program with a regular concert season featuring its signature ensembles: The Thomson Singers, Junior Concert Band, Jazz Band, and The Thomson Senior Concert Band. There is also a Music Executive which facilitates and assists in concert planning and music events.