Thornhill High School opened on the air force base in Gwelo, Rhodesia (now Gweru, Zimbabwe) in January 1955.
In January 1958, the school moved to its present site in Gweru.
The school motto Per Spinas Ad Culmina (Through the thorns to the hilltop) was composed by Frank Taylor, based on the air force motto Per Ardua Ad Astra (Through effort to the stars).
The school also offers sport, including hockey, cricket, soccer, volleyball, netball and rugby.
Alumni web site https://thornhillhigh.neocities.org/