"We want young people energized in the way that you all are, because we know that American brainpower in science and math has always driven this country's prosperity," she told the group after the two winning teams had received their trophies. "We are going to need you."
Mrs. Obama said that the nation depends on the next generation of innovation and challenged the students to help build the future of medicine, clean energy and security.
During the middle school competition Mrs. Obama asked 17 bonus questions of the two finalist teams. Her questions covered multiple areas of science, including potential functions of the appendix, what the letters and numbers stand for in the H1N1 flu virus, the protein content of blood and studies on the San Andreas fault in California.
Afterward she joked that she had to study just to properly read the questions.
Albuquerque Academy from Albuquerque, N.M., won the middle school science bowl.
Earlier, first-time competitors North Carolina School for Science and Mathematics from Durham, N.C., won the high school competition.
Regional science bowl winners from 105 middle and high schools traveled to Washington for the national competition. The teams represented 42 states, DC, Puerto Rico and the U.S. Virgin Islands.
Energy Secretary Steven Chu joined Mrs. Obama, serving as the senior science judge during the middle school competition.