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First Lady Michelle Obama attended two of America's finest schools - Princeton University and Harvard Law School.

But on Tuesday she told a group of underprivileged Washington, DC high schoolers - many of whom are hoping to be the first in their families to go to college - that she once faced many of the same challenges and doubts as they do.

"I was willing to do whatever it took for me to go to college," Mrs. Obama said. "Get this - some of my teachers straight up told me that I was setting my sights too high. They told me I was never going to get into a school like Princeton. Nobody was going to take my hand and lead me to where I needed to go. Instead, it was going to be up to me to reach my goal. I would have to chart my own course."

Speaking to sophomores at Bell Multicultural High School, Obama talked about riding the city bus across Chicago an hour each way to high school, forming close relationships with her teachers and administrators, pursuing leadership opportunities, and studying to have the strongest academic record possible so that she could attend her dream school - Princeton.

Mrs. Obama was touting her husband's "North Star" Goal, that by the year 2020 America will once again have the highest proportion of college graduates in the world.

But she told the students that "no matter what the president does, no matter what your teachers and principals do, or whatever is going on in your home or in your neighborhood, the person with the biggest impact on your education is you."

"More than anything else," she added, "meeting that 2020 goal is going to take young people like all of you across this country stepping up and taking control of your education."

Mrs. Obama stressed that a commitment to education would create a better future for both the students and the country, no matter the obstacles.

"We come with that internal doubt thing in our heads, where we wonder whether we're we good enough, are we smart enough, are we prepared for these opportunities? And I found that, for me, I had to get out of my own way," she said. "Most importantly, when I encountered doubters, when people told me I wasn't going to cut it, I didn't let that stop me - in fact, I did the opposite. I used that negativity to fuel me, to keep me going. And at the end, I got into Princeton, and that was one of the proudest days of my life."

"It is not your circumstance that defines your futures," she said, "It's your attitude."