While little is known of Sarah's early life, she was already a schoolteacher when she married a master saddler by the name of Henry Heap on 30 March 1893 at Stalybridge, Lancashire.
Although she tried to create a physical training college for women in Auckland, that effort failed and she decided to establish herself as a teacher.
There, she played an essential role in shaping the country's new system of physical instruction and medical inspection, which was introduced under the Education Acts of 1912 and 1914.
In addition to lessons in drill, where girls swung dumb-bells, marched and performed exercises to her piano accompaniment, she organised school games, took dancing classes and gave instruction in first aid and home nursing."
[1] During the First World War, Heap took responsibility for training the grammar school squad of the Women's National Reserve of New Zealand.