Good history of the role that women of color played in engineering, leading up to the well-known lunch counter sit-ins and US civil rights movement.

Very insightful analogy about racial segregation, comparing it to an electric fence -- even when the power is turned off, people are hesitant to climb over it. The self-selection of taking yourself out of a race before it's even begun, because of the belief that you can't win or the odds are stacked against you is powerful and real.