Johnson will replace Manuel J. Rivera, who accepted the position in January but is now taking a job as the top education adviser to New York state.
According to the Boston Globe, Johnson had been considered for the post previously but refused on be interviewed for the job.
From the story: "Johnson, who has overseen a school system more than twice the size of Boston's since 2003, was the best of several finalists to lead the 57,000-student school system, [Boston Mayor Thomas] Menino said. He cited Johnson's success in improving the performance of minority students in Memphis and her reputation as a superintendent who includes parents and community leaders in decision-making -- two characteristics that Boston parents, activists, and school officials have said they wanted to see in the next public schools chief.
"'She'll give us the leadership we need in these schools,' Menino said. 'I think she'll bring us to the next level. We're very fortunate to attract a talent as strong as Carol.'"
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