MELISSA BLOCK, HOST:
For years, Miami-Dade County Public Schools faced problems common to many urban schools: low attendance, high dropout rates, poor grades. But since 2008, Alberto Carvalho has been in charge of the nation's fourth largest school district, and there've been some noticeable improvements in Miami schools. More students are graduating, fewer are dropping out, test scores are up and the district's budget crisis has faded.
NPR's Claudio Sanchez has this profile of the man some call a miracle worker.