The school is located at the corner of Fordwich Crescent and Islington Avenue. The split level school is located next to the Humber River. The school building is a square complex with a curved auditorium. This school is very high in academics and in athletics. In 2005 Thistletown C.I.'s varsity hockey team won the city championship and the year before they went undefeated all season.
The school was erected between 1956 and was constructed in the late 1960s. Graduates include Steve Durbano, former St. Louis Blues defenseman, Colin Paterson, former Calgary Flame, and Mike Katrycz, on-air personality in the GTA.
Athletic triumphs include the Etobicoke senior football championship, earned in 1969 by defeating the Etobicoke H.S. Rams, led by John Villiers, Al Thomas, John Griffin and Mark Eaves. The senior basketball team reached the T.D.I.A.A. finals (consisting of all the outlying boroughs of the metropolitan area in those days, including Etobicoke, Scarborough, North York, East York, and York) in 1972 and 1975, only to suffer defeat at the hands of the George Harvey Hawks. Prominent contributors from that era include Edgar Jaunzarins, Steve and Ross Quakenbush, Trevor Bennett, and Ken King.