After a tumultuous few years, Montgomery County Public Schools is going through big leadership changes and the general elections in November may bring more. Among them is the new president of the teachers’ union, MCEA: David Stein, a veteran math and statistics teacher in Montgomery Blair High School’s famed STEM program. Sunil Dasgupta talks with Stein about how he sees the challenges ahead for MCPS and for public education. Music by Alexandria alt-rock band Jackie and the Treehorns.