Like many other principals across the city, Edward Tom has developed something of a nervous habit. Each morning, when he switches on his computer at the Bronx Center for Science and Mathematics, he checks to make sure his school has the same amount of money it had the night before.
Mr. Tom is not a principal one would normally suspect of anxiety. Eighty-three percent of the students in the senior class at his small South Bronx high school graduated this spring, well above the 52 percent borough average. More than three-quarters of them enrolled in four-year colleges, winning $3 million in scholarships.
"These are the students people said couldn't learn," Mr. Tom, who has been principal since the school opened in 2005, said proudly.
But budget cuts are coming, even if it is too soon to say exactly when and how much. Most city agencies have been asked to submit plans for cost savings; the Department of Education has been asked to prepare for a 1.5 percent midyear cut and a 4 percent cut for next autumn's entering class.
While it is not known how much individual schools will be asked to shave, principals like Mr. Tom are preparing for the worst. It is part of their role, since 2007, of managing a large portion of their own operating budgets.