It’s really no secret that the United States’ public education system needs an overhaul. But writer and director Davis Guggenheim still manages to make “Waiting for ‘Superman’” an informative and heartbreaking documentary about public education.

The film focuses on the United States, looking at so-called “dropout factories” and how American students consistently fall behind in math and reading skills. By graduation, many of the students in the United States are several grade levels below proficiency.

The movie turns its attention to educational reformers like Michelle Rhee, recently resigned head of Washington, D.C., public schools, and Geoffrey Canada, founder of Harlem Children’s Zone and several other charter schools in low-income areas throughout the country.

In addition to interviewing heavyweights in education, teachers’ union leaders and special interest groups, Guggenheim also interviewed five students applying to charter schools and followed them as they sat through the nerve-wracking entrance lottery.

Guggenheim is no stranger to documentaries; in the first 10 minutes of this film, he refers to his first documentary, “The First Year,” about first-time teachers. He also directed the film “An Inconvenient Truth.”

The movie does well in taking the lives of children usually deemed “statistics” in terrible schools and making their stories compelling. Rather than looking at how unfortunate their lives seem or the slim chance they have of making it to good schools, the film looks at the dreams of the children. It also takes a look at the sacrifices that their parents and guardians make to better the lives of their kids, such as a mother working three jobs to put her daughter through Catholic school.

Where many documentaries get heavy with statistics, “Waiting for ‘Superman’” turns them into amusing cartoons of children moving on to careers, students being left behind by antiquated education standards and terrible but tenured teachers being traded between schools because they can’t be fired. The cartoons are engaging and keep the film from feeling too numbers-based.

The most interesting, inspiring and heartbreaking parts of the documentary, however, are the interviews with the students. Washington, D.C., fifth-grader Anthony wants to go to a charter school so he can build a better life for himself. Daisy is a fifth-grader in Los Angeles who wants to become a doctor and go to college — something her parents never did.

The movie falters when it tries to mock politicians. The majority of the documentary is a bittersweet look at children trying to get an education in areas where it’s nearly impossible. When Guggenheim shows footage of presidents signing education bills into law, and in the case of President George W. Bush, making grammatical mistakes as he introduces the No Child Left Behind Act, the movie gets preachy. This isn’t a Michael Moore documentary. It doesn’t need to bash presidents to be effective.

While the documentary doesn’t really reveal anything revolutionary about the schools in the United States, it’s still a staggering look at the statistics of the failure of American education and a touching look at what families will go through to try to make their childrens’ lives better.

“Waiting for Superman’” was written and directed by Davis Guggenheim.