[4][5] In 1894, Timlow and her sisters started a girls' boarding school named Cloverside in Montclair, New Jersey,[6][7] after their father's death left them in need of an income.

[12] She was traveling in Germany with five students in summer 1914, when German mobilization for World War I began, and she had to guide the party of girls to safety.

[16] "Never have I ever read a finer or grander description of a thunderstorm," wrote one reviewer of Timlow's The Heart of Monadnock.

[17] Timlow was a member of the Daughters of the American Revolution[18] and active in the Parent Teacher Association in Washington.

[19] She advocated smaller class sizes, older teachers, and teaching more study skills than "miscellaneous knowledge.