PHILADELPHIA — Just a month after Detroit became the largest American city to file for bankruptcy, and with major cities like Chicago and Los Angeles struggling, this former manufacturing behemoth is also edging toward a financial precipice. But here the troubles are centered on the cash-starved public schools system.

The situation is not as dire yet as Detroit’s. There is no talk of resorting to bankruptcy. But the problem is so severe that the city agreed at the last minute on Thursday to borrow $50 million just to be able to open schools on time. Even with that money, schools will open Sept. 9 with a minimum of staffing and sharply curtailed extracurricular activities and other programs.

“The concept is just jaw-dropping,” said Helen Gym, who has three children in the city’s public schools. “Nobody is talking about what it takes to get a child educated. It’s just about what the lowest number is needed to get the bare minimum. That’s what we’re talking about here: the deliberate starvation of one of the nation’s biggest school districts.”

Superintendent William R. Hite Jr. had been threatening to delay opening schools if the city did not come through with the $50 million, which he said was necessary to provide the minimum staffing needed for the basic safety of the district’s 136,000 students. In June, the district closed 24 schools and laid off 3,783 employees, including 127 assistant principals, 646 teachers and more than 1,200 aides, leaving no one even to answer phones.