Presidential candidate Julián Castro: "You can look this bad in high school and still go places"

Presidential candidate Julián Castro revisits his San Antonio, Tex. high school with reporter Libby Casey to talk about his formative years. Julián and his twin brother Joaquin both entered public service after seeing their mother dedicate her life to improving their community of San Antonio. Julián was the youngest person elected to the San Antonio City Council, won three terms as the city's mayor, and served as President Obama's Secretary of Housing and Urban Development. His brother, Joaquin, is a Congressman. Now Julián Castro is running to become the next president of the United States. He's part of a crowded Democratic field of 2020 candidates including Joe Biden, Elizabeth Warren, Kamala Harris, Cory Booker and Pete Buttigieg trying to unseat President Trump.

When Julián Castro goes home to San Antonio and tours his old high school, he remembers being a nerdy student who graduated a year early, and the time he spent as a substitute teacher when one of his students hit him in the head with a paper ball.

Washington Post reporter Libby Casey covers politics and takes you behind the scenes of journalism in her series "How to be a journalist." Watch the series

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