One knock on charter schools is the lack of diversity -- filled with either all minority and low-income students, or mostly affluent students. Some charter schools see a benefit to pulling students from both sides of the tracks. Above, students at a charter school in Harlem in New York City. - 

Todd Dickson is trying something a bit unusual for a charter school founder. He’s recruiting students to Valor Collegiate Academy from working class neighborhoods, and Nashville’s wealthiest enclaves.

Dickson addresses a crowd of families with the means to pay private school tuition. But the parents in this room are prepared to give public schools a chance.

A father himself, Dickson also helped start Summit Prep in the San Francisco area. There are similar charters in places like Denver and New Orleans.

Their belief is these charter schools is that all income levels benefit from learning side-by-side, helping them understand multiple perspectives.

“It’s much more authentic and easy to learn to do that well if you are learning with kids who really have different experiences and different backgrounds than you do," say Dickson

The trick is getting everyone in the same classroom.

Jennifer Erickson worries her daughter is being raised in a bubble at her private school.

 “I mean to me, education isn’t just about books. It’s about being well rounded in all areas," says Erickson. "That is a very big piece that my daughter is not getting. Of course, there are negatives that come with that.”

Well-off families often question whether these charters can really push high performers while trying to get disadvantaged students doing double time.  It’s not uncommon for some to come into middle school reading at a second-grade level.

At a recruiting session in an immigrant community center, an interpreter translates in a whisper to a Hispanic mother.

These parents here aren’t so worried about raising kids in a bubble. They’re looking for opportunity.

Hafza Mohamed’s son attends a struggling school now.

“I want him to go forward, not backward," says Mohamed.

A few of these charters with integrated student bodies have been successful getting everyone prepared for college. But advocates say there’s a bigger benefit that doesn’t show up on a report card -- relationships that span the divide between rich and poor.