It’s only a few weeks until students head back to school. In Boston, if this year is like last year, and like many others before that, there will be fewer of them in classrooms this fall. 

Boston has been booming economically, a fact reflected in big population growth in recent decades. The city now claims more than 675,000 residents, according to the 2020 Census, an increase of more than 100,000 from 1980, when Boston’s post-World War II population bottomed out at 563,000. But that population surge has been accompanied by another trendline going the opposite direction: A steep decline in the population of school-age children in the city. In just the two-decade period from 2000 to 2020, Boston’s population of school-aged kids aged 5 to 17 fell by about 10,000 – going from 80,000 to about 70,000. 

It’s a troubling trend, says Will Austin, founder and CEO of the Boston Schools Fund, a nonprofit working to improve quality in Boston schools. “You can define families in many different ways, but the reality is that kids do make neighborhoods,” Austin said on this week’s episode of The Codcast. 

Austin, 43, grew up in Dorchester and is raising his three school-aged children with his wife in Roslindale. Boston neighborhoods are far different from those of his youth. When he was growing up, Austin said, there were 18 school-age kids on his street, all within three years of age. There was a kind of “community in that space” that is increasingly hard to find in many Boston neighborhoods today. 

There are lots of factors at play, said Austin, but chief among them are the soaring cost of housing in the city and the complicated student assignment process and uneven quality of schools in the district system.