[3] Forsythe was born in Newton, Massachusetts and raised in Cortland, New York.
[4] She attended Swarthmore College, where she met her future husband George Forsythe, and earned her bachelor's degree in mathematics.
Although an exceptional student, she was unable to continue in the program because the dean did not approve of female mathematicians and cut her fellowship support.
[5] She eventually left Brown and completed her master's degree at Vassar College in 1941 while serving as an instructor.
[3] In 1978, Forsythe and a co-author, E. I. Organick, published Programming Language Structures.