The Obama girls could have visited Robben Island in 2011 when they accompanied their mother on her visit to South Africa, but the trip was scrubbed at the last minute due to rough seas.
Michelle Obama says she definitely would take more risks if she could go back and relive her teenage years.
She avoided getting too specific, though, saying simply that she'd try more things and travel more.
"I wouldn't be as afraid as I was at that age to fail," she said in Johannesburg during a Google+ Hangout chat involving scores of young people in Africa and several cities across the U.S., including New York City, Los Angeles and Houston. Singer-songwriters John Legend and Victoria Justice also participated.
After some of the students seated on stage with the first lady were asked to name their dream jobs, the question was then put to her.
Mrs. Obama didn't identify her dream job, but said that back then she could never have envisioned participating in such a forum. She often has said she never saw herself becoming first lady, either, and used her example to try to inspire the audience. She told them to keep their dreams big and embrace failure.
"Don't take yourself out of the game before you even start, because there's no telling what life has in store for you," Mrs. Obama said.
Associated Press writers Nedra Pickler in Johannesburg and Darlene Superville in Washington contributed to this report.
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