The city let residents who are at least 12 years of age decide which six projects (out of two dozen) to fund. Similar exercises of what's known as participatory budgeting -- including the participation of minors -- have proven popular overseas and have been tried in a few other U.S. cities, including neighboring Boston, Chicago and New York City.
Twelve is young, but the idea of lowering the voting age to 16 has been debated for years and now appears to have some momentum.
"Everyone says they're for kids, but spending on kids continues to decline because there's not any power behind it," said Bruce Lesley, president of First Focus, a group that advocates for families and children at the federal level. If tyounger teenagers voted, "politicians would then actually have to talk to kids to get their votes for the first time. They might pay attention to their issues."
A group called Generation Citizen has raised nearly a quarter of its $1 million goal for its campaign to lower the voting age in local elections to 16 nationwide. Other groups have pushed similar ideas, but haven't set such ambitious fundraising targets.
"It's amazing to see the sea change," said Alex Koroknay-Palicz, president of the National Youth Rights Association. "We've seen years and years and years of being the only organization in the country working on this."
The idea has been around for at least a decade, but critics' concerns that young teens lack the intellectual maturity to vote have previously killed any traction it may have had. In the last two years, though, two Maryland municipalities, Takoma Park and Hyattsville, started letting 16-year-olds vote in local elections. And now bigger cities, including San Francisco and Washington, D.C., and at least two states -- Colorado and New Mexico -- are seriously considering such proposals.
Proponents of lowering the voting age frame the issue as one of equal representation.
"We live under the same laws and have an interest in seeing leaders that represent us and our interests," said Koroknay-Palicz. "Sixteen-year-olds are not different than any other Americans, and they're currently not represented."
Koroknay-Palicz also argues that extending the franchise to younger teens would instill better voting habits in a country where turnout for all ages is abysmally low for local elections -- often well under 20 percent. Young adults in their early 20s away at college don't necessarily feel connected to the places they're living, he says. A 16- or 17-year-old, by contrast, is more likely to have deep roots and strong opinions about their community. In Takoma Park's first elections after lowering the voting age, 16- and 17-year olds voted at double the rate of those 18 and up. (Admittedly, only 59 of those aged 16 or 17 turned out.)
The most common argument against lowering the voting age is that younger teens won't make wise choices at the ballot box.
"Those too fragile to handle different opinions are too fragile to participate in politics," wrote Glenn Reynolds, a law professor and prominent conservative commentator, last month. "So maybe we should raise the voting age to 25, an age at which, one fervently hopes, some degree of maturity will have set in."
But Laurence Steinberg, a psychiatrist at Temple University who is a leading expert on adolescent development, wrote last year that 16-year-olds are fully capable of "making informed and reasonable political decisions." Supporters of lowering the voting age also argue that it's easy to find evidence of adults of any age who make lousy or ill-informed political choices.
Many other countries -- such as Brazil, Ecuador and Indonesia -- let minors vote in elections. After allowing citizens as young as 16 to vote in an independence referendum in 2014, Scotland gave them the right to vote earlier this year. On Monday, however, the British House of Lords refused to allow 16-year-olds to cast a vote on a referendum about the European Union.
In the U.S., the voting age was lowered in 1971 from 21 to 18 with the 26th Amendment. The argument at the time was that if young men were old enough to fight and die in Vietnam, they were old enough to vote. Most states now let people preregister to vote at 16 or 17 if they will be 18 in time for the next general election.
It's still an uphill fight, but there does appear to be some momentum in favor of allowing younger people a direct say in their own political futures.
"If you want to be Democratic," says Wall, the Rutgers professor, "everyone who knows what voting is should be able to vote."