Back in 1943, Euphemia Lofton Haynes became the first ever black woman to receive a PhD in mathematics, at the age of 53. (Her dissertation, which I won’t attempt to decipher, is titled “The Determination of Sets of Independent Conditions Characterizing Certain Special Cases of Symmetric Correspondences.”) A fourth-generation Washingtonian, she spent 47 years teaching math in D.C.’s public schools; in 1959, she became head of the city’s Board of Education, and was instrumental in desegregating the very high school she attended four decades prior. She also established a mathematics department at her teachers’ college, and established a scholarship fund upon her death. In other words, she was an outspoken critic of injustice, and a creator of new opportunities for young people to enter the field that she saw so much beauty in.
The race and gender disparity in STEM fields is caused by a lot of factors, both financial (disparities in school funding) and sociological (bad media representation), but one thing it’s not caused by is a lack of real-world role models. You can celebrate math today by helping bring these role models into view where they belong.