How does Sally Ride show self-discipline?

Sally Ride is well known as the first American woman in space. She became an astronaut in 1978. She flew in the space shuttle Challenger. When she was young she did not have a lot of self confidence. Although she did well in mathematics in high school she was not sure she would succeed at it in college. She attended an all girls school named Westlake. She had self discipline by studying and excelling in trigonometry, calculus and chemistry. That gave her the confidence to become a physics major which led to her being an astronaut.