MEMPHIS, Tenn. (AP) — Rewarded with the president of the United States as their commencement speaker, the graduating seniors at Booker T. Washington High School got the same advice a young Barack Obama once got himself: Keep pushing. "You've always been underdogs," the president told the cheering students, clad in green and yellow gowns, from a school where academic scores and graduation rates have soared despite tough conditions in the community. "Nobody's handed you a thing.