[1]: 6  In 1886 she went to Notting Hill High School for Girls, leaving in 1891 to enter University College Wales, Aberystwyth, where she studied mainly philosophy.

[2] She earned a Bachelor of Arts (BA) degree in Mental and Moral sciences from the University of London in 1894.

[3] From 1894 to 1897 Edgell taught high school in Sunderland and Blackburn, earning a teaching diploma from the University of London in 1896.

[5] When she returned in 1901 from her year's leave of absence at the University of Würzburg, she set up one of Britain's first psychological laboratories at the college.

[2][4] Edgell's early research projects included collaborating with the physiologist William Legge Symes to calibrate the Wheatstone-Hipp chronoscope, a piece of equipment used in experimental psychology to measure reaction time.

[3][5] She wrote two textbooks, Mental Life and Ethical Problems, introducing applied psychology to social studies and nursing students respectively.

[3] Edgell was one of the earliest members of the British Psychological Society, and presented a paper on time judgement at the association's fifth meeting in 1903.

The Oxford Dictionary of National Biography describes her as a "standard-bearer for psychology" and a "conscientious and painstaking teacher who cared deeply about the education, welfare, and future careers of her students.