When Mayor Bill de Blasio approved New York City's $75 billion budget last week, his signature on a key aspect of the spending plan signaled the latest evidence of a major shift in how school districts are approaching feeding their low-income students.

Included in New York City's new budget agreement is a plan to spend $6.25 million to provide free lunches to all the city's public middle school students -- regardless of their income -- as part of a pilot program beginning in the fall.

The lunch program's approval was part of a compromise with advocates who wanted all public school students to receive free meals. It was praised by New York City Council Speaker Melissa Mark-Viverito as a plan that "will help keep our schoolchildren fed, allowing them to focus on learning and not where their next meal will come from," the New York Daily News reports.

Community Food Advocates, an advocacy group that has pushed for free lunch for New York students through its Lunch 4 Learning Campaign, also praised de Blasio and Mark-Viverito for backing the program and described it as "lay[ing] the groundwork" for all the city's students to enjoy free lunch with the goal of reducing their level of food insecurity.

"This is an incredibly transformative moment for middle school students who will grow up with a school lunch program where everyone eats on equal terms -- the poverty stigma attached to school lunch will be erased," Community Food Advocates executive director Liz Accles said in a statement.

While New York is the largest city to adopt a so-called universal free lunch program, it is far from the first school district to do so.

The New York lunches are an outgrowth of a federal pilot program that offered a "community eligibility" provision to schools in six states and Washington, D.C. The first stages of the pilot program, outlined by the Healthy, Hunger-Free Kids Act of 2010, began in 2011.

Districts where at least 40 percent of students come from families that already receive some sort of federal assistance, such as food stamps, automatically qualify to offer free lunch to all their students under the program. As of May 1, it is now available to all states.

In high-poverty areas where the program has already been instituted, supporters say it has increased participation in schools' free lunch programs while also reducing the paperwork burden -- and associated costs -- for both individual families and the district itself. Supporters of so-called "single-payer" lunch say reduced stigma for older students who don't want to be seen as poor by their peers is also a factor in the increased participation.

According to a 2013 report from the Center on Budget and Policy Priorities and the Food Research and Action Center, free lunch participation increased 13 percent -- and breakfast participation was up 25 percent -- in the first two years of the program in Illinois, Kentucky and Michigan, the three states where it first launched.

Boston Public Schools will also be taking part in the program for the first time in the 2014-15 school year.

Still, the program is not without its critics. A researcher with the conservative Heartland Institute claimed during a Fox News appearance that the community eligibility free lunch option is contributing to youth obesity rates, MSNBC reports.