'Greenwood was not only a highly original physiological investigator; she also spent a considerable amount of time training a new generation of women scientists at Girton and Newnham. She was initially been somewhat reluctant to take on work that might distract her from her research. On being offered the role of Demonstrator of Physiology at the Balfour laboratory in 1884, she wrote to the Mistress of Newnham College Eleanor Sidgwick that:

My first thought would have been about the Studentship and the right [means] of having any time except in the work for which it is given. But that is made unnecessary by the decision of the Committee [of the Balfour Laboratory]. Therefore I can only say that while taking the post with some doubt of myself I will do all I can to make the teaching thorough and successful.

I hope it will mean no lessening of research, but only a better arranging of the day's work.

She nevertheless found that the post required her to invest a considerable amount of energy.'