The document summarizes research on gender differences in STEM performance and participation from high school through careers. It finds that while girls have made gains in high school math/science credits and GPAs, they are less likely than boys to take AP STEM tests or declare a STEM major. Social and environmental factors like growth mindsets, stereotypes, and biases in university environments contribute to ongoing underrepresentation of women in many STEM fields. Addressing these systemic issues through role models, clear standards, and bias awareness is important to achieving full participation and success for women in STEM.