Last week’s surprise resignation of the state education commissioner, MaryEllen Elia, leaves New York schools at a crossroads. Depending on whom the Board of Regents selects to succeed Elia, the commissioner can serve as a force for reform or for preserving a troubled status quo.

The next commissioner will shape crucial policies on curriculum, testing and accountability, graduation requirements and the relationship between government and private schools.

New York’s education commissioner is the highest-ranking state-government official not directly answerable to or appointed by the governor. ­Under a system dating back to the immediate post-colonial era, it’s up to the 17-member Board of Regents to hire the commissioner.

Working with the Regents, the commissioner has broad regulatory oversight of New York’s more than 700 school districts and the boards that govern them, as well as licensure of teachers and other professionals.

Elia, a former superintendent, spent most of her four years as commissioner treading water. She generally maintained all that is best and worst about New York’s $70 billion school system.

One Elia misstep was issuing regulations that could allow unprecedented intrusion by local school officials into the affairs of nearly all private and parochial schools — overreach that goes far beyond improving admittedly lackluster academic curricula at some yeshivas.

A more important issue is graduation rates. Since she submitted her resignation, the Board of Regents is reportedly considering scrapping Regents’ exams in order to artificially boost graduation rates, and that’s where her successor should focus his or her energies.

For starters, the next commissioner should acknowledge how recent improvements in graduation rates don’t mean that growing percentages of students are actually college- or career-ready.

For example, the improvement in statewide graduation rates of 9.5 points over 10 years, to 80 percent, doesn’t correlate with actual readiness for college or career, which has hovered more than 40 percentage points lower.

Yes, Elia’s successor should guide a rethinking of graduation requirements that have become overly skewed to four-year college preparation at a time when lucrative skilled blue-collar jobs are going unfilled. Such rethinking, however, shouldn’t come at the expense of watering down standards for students heading to college.

Rather, the goal should be college and career readiness — period — and the state should retain Regents exam requirements as at least one pathway for students.

It’s also crucial for the next education commissioner to tackle the state’s controversial Common Core curriculum and the integrity of the standardized testing system, whose validity has been undermined by aggressive grade-curving and a boycott movement that has led large numbers of students to opt out of testing, especially on Long Island.

The next education commissioner also should be more willing to tackle the spiraling cost of public education in New York — which, at more than $23,000 per pupil, or 89 percent above the 50-state average, leads the country. Pushing back against the Regents’ tendency to demand more than the state can afford, the commissioner should present legislative and regulatory options to spend more effectively and save money for taxpayers.

Last but not least, the commissioner must be a voice for disadvantaged, low-income children who are all too often consigned to failing, substandard public schools. Charter schools and private K-12 scholarships have proved to be highly effective ways to provide true equality of opportunity — and quality education — to kids otherwise poorly served by the school districts in which they live.

Expanding and protecting school choice while improving traditional public education aren’t mutually exclusive priorities: The next commissioner should embrace both.

To be successful, the commissioner should have a proven track record of experience and accomplishment as an educator, manager and skillful navigator of diverse and competing interests. It’s a tall order, to be sure.

Albany’s legion of teacher unions, school-professional associations, special-interest advocates and the politicians they incessantly lobby remain focused primarily on the interests of adults employed by the education system. It sounds trite, but it’s true: The next education commissioner must rise above the noise and put children first.

Peter Murphy is senior fellow for education at the Empire Center for Public Policy in Albany.