Edna Kramer was born in New York City, the daughter of Jewish immigrants. She graduated summa cum laude from Hunter College in 1922. In 1930, she became only the third woman to earn a doctorate in pure mathematics from Columbia University, at the same time teaching at DeWitt Clinton High School in the Bronx and Wadleigh High School. She continued her studies at the Courant Institute of Mathematical Sciences at New York University and at the University of Chicago. In 1935, she married Dr. Benedict T. Lassar, a French teacher.
From 1948 until her retirement in 1965, Edna Kramer Lassar was professor of mathematics at the Polytechnic Institute of New York. She also taught at various other colleges and universities. Her greatest work is considered to be The Nature and Growth of Modern Mathematics (1970).