Several weeks into a new school year, William R. Hite Jr. has his elevator pitch perfected: The Philadelphia School District is in the best shape he's seen during his superintendency.

The 130,000-student system carried a small financial surplus into the new school term. Officials were able to buy new textbooks for the first time in years, and they were able to restore nurses, counselors, and some art and music teachers.

But Hite and district chief financial officer Uri Monson told a room full of Center City businesspeople Tuesday that what they lack is the ability to guarantee that condition in the long term.

"It's a lot more stable - for right now," Hite told members of the Central Philadelphia Development Corp. who gathered at the Union League.

District expenses are growing far faster than revenues, and because the school system has no control over those revenues, it projects a deficit by 2019 that balloons to $583 million by 2021.

Hite's administration hopes to demonstrate academic success and fiscal prudence as a way to convince funders - including government bodies and businesspeople - that the public schools are worth investing in.

"You can't yo-yo educational investments," Monson said. "You can't give a nurse and a counselor one year, and then take them back."

Hite acknowledged the dichotomy inherent in his job: presiding over a system that is largely struggling and in many cases losing students, that at the same time has pockets of high demand and strong performance.

Center City schools - nominally the focus of Tuesday's event - are bursting at the seams.

One audience member told Hite that her daughter attends Meredith Elementary in Bella Vista, where the two fourth-grade classes are overcrowded, with 37 students each.

Hite, whose home is in that school's catchment, said he was recently discussing the problem with parents and hopes to come up with a creative solution.

"There's no expanding at Meredith," he said. "It's a very popular and high-performing school that's doing great work. We want to make sure they have the resources that they need."

Hite also gave a preview of state-test results, scheduled to be released this week. Philadelphia students' scores rose for the second year in a row, he said.

One audience member applauded the district's move to reinstate some art and music teachers lost in prior budget cuts, but asked about science, technology, math, and engineering. Hite said that was a focus, too.

On the first day of school, the superintendent visited William Cramp Elementary in North Philadelphia, where he saw a class of third graders coding. More children in elementary schools have those opportunities now, Hite said. But many others do not.

Hite and Monson underscored that one of their chief obligations is to ensure strong schools all over the city, not just in its center.

"We have to do much better at our comprehensive neighborhood high schools," Hite said. "Many of those offerings are not available at our neighborhood high schools."