Blue Mountains Grammar School, abbreviated as BMGS, is a dual-campus independent Anglican comprehensive co-educational early learning, primary and secondary day school, located in the Blue Mountains suburbs of Wentworth Falls and Valley Heights, New South Wales, Australia.

BMGS was founded in 1918 as Blue Mountains Church of England Boys Grammar School, in Springwood.

[1] From this grounding Deane built the school into a multi-classroom premises in Springwood, which throughout the 1920s saw successes in student numbers and education initiatives.

During the war years, the number of enrolments at the school kept up quite well, given that most parents wanted to send their children out of the Sydney area.

Vaping has also been an issue at the school though it appears to have been bought under control since a student passed out in the boys toilet in 2022 [7]