Education reform in America is among the hottest of hot-button issues, the compelling documentary "Mitchell 20" reminds us. Budget cuts, debates over national standards and arguments about accountability are all tugging at our basic obligation to teach kids.

Add to those pressures, at least in some communities, high poverty, low resources and questionable school-district management, and the challenges to education on a local level become profound. To whom do we look for answers?

"Mitchell 20" offers an impassioned answer: Invest in teacher performance and teacher leadership.

The film's title refers to Mitchell Elementary School in the high-poverty Isaac School District in Phoenix, Ariz. In 2007, a determined teacher at Mitchell, Daniela Robles, earned her National Board Certification, no easy feat but a career marker that, Robles says, sharpened her skills and commitment to students.

Robles encouraged the rest of the faculty to do the same, and got 19 bites. The filmmakers, Andrew James Benson and Randy Murray, spent the next couple of years or so following the efforts of those educators (a truly diverse bunch: Latino, white, Asian, Indian) as they underwent a grueling process of pursuing certification on their own time.

Not everyone succeeds, but something larger is achieved. Mitchell's teachers bond over the experience and, they say, pull together as a team to lift the school to a higher standard.

The film argues that empowering teachers, and keeping those teams together, is a form of nonbureaucratic, bottom-up leadership that could make a huge difference to education. (It helped the Mitchell group to have the considerable expense of certification partly covered by district money, instead of — more typically — entirely out-of-pocket.)

That point and many others in "Mitchell 20" are made in a strong spirit of advocacy that others, with different views about solutions, might dismiss. But if there is anything objective that can be said about education it's this: Good teachers matter.

Tom Keogh: tomwkeogh@gmail.com