The students at Ada — Adies, as they affectionately call one other — are in many ways representative of Seattle’s churning, anxious arc of growth and change. The 61 women who have graduated since the school’s founding in 2013 have been drawn here from across the nation and several other countries. Tuition is free for applicants who pass the rigorous admissions process, with costs underwritten by Seattle tech giants like Amazon.

Of the 13 most populous counties in the nation, King County in the Seattle metro area is second only to Brooklyn in the highest percentage of residents age 25 to 34, part of the biggest demographic wave since the baby boom, according to census data. And Seattle is luring those millennials from all over, with King ranking second among big counties in the percentage of people who moved here within the past year from another state.

But even in a place of alluring opportunity, the Adies, like Ms. Boshart, mirror their generation’s anxieties.

Many are terrified of debt and deeply worried about their economic future. Student loan burdens sharply increased nationally during the recession, according to a report by the Federal Reserve Bank of Atlanta, more than tripling to $1 trillion from 2004 to 2012. Unemployment for people under 25 is more than twice the national rate, which has made many of those loans harder to pay off. Millennials have postponed marriage and decisions about where to live and what careers to pursue, the Federal Reserve study said, far longer than previous generations, often out of economic necessity.