She was Dean of Women (effective 1932) and taught Greek and Latin at Swarthmore College, where she was a member of the faculty from 1916 to 1947.

[3] She held the Bennett Fellowship in Classics from 1912 to 1914, and completed doctoral studies at Penn in 1915, with a dissertation titled "Roman Craftsmen and Tradesmen of the Early Empire".

[4][5][6] Brewster taught Latin, French and English at Chester High School after she graduated from Swarthmore in 1907.

[3] In 1919, she addressed an audience at the Philadelphia High School for Girls, saying "It is as stupid to oust ancient history from the schools in favor of American and modern European history as it would be to knock out the first two stories of a skyscraper and expect the structure to stand.

[22] Her body was found in a closet, with a bottle of sleeping pills, after she had reportedly expressed concern over her declining health.