BETSY DEVOS begins her tenure as U.S. education secretary with the dubious distinction of being the only Cabinet member in history to need the tie-breaking vote of the vice president to win Senate confirmation. That she barely squeaked by — due in no small measure to her poor performance at her confirmation hearing — hopefully impresses upon her the need to do some homework and assemble a competent team.

We say that not as critics but rather as believers in a principle she has espoused: the need to open up more educational choices and opportunity for American families who are denied options that the more privileged — including some of those who have been most overwrought in their opposition to Ms. DeVos — take for granted.

The debate about Ms. DeVos has been unprecedented for someone heading up a department that represents a minuscule portion of the federal budget. But much of it centered on her status as a billionaire, her silly comment about the need for school personnel to be armed against grizzlies and her inability to answer fundamental questions about educational policy and practice. We don’t dismiss concerns raised by her faltering performance or the disservice done by Republicans in cutting off legitimate questions from Democrats. But now that she has been confirmed, the focus must shift. Most critical will be how she — a passionate advocate of school choice in pretty much all forms — aims to reform what she calls the “one-size-fits-all model” of schooling that she rightly says is not equipped to meet the needs of every child.

We would urge her to take a good, hard look at the education system in the District, where a commitment to public schools (both traditional and charter) and the judicious use of private school vouchers to help economically disadvantaged students have given parents options and helped improve student outcomes. She should pay particular attention to the hard lessons D.C. officials learned in the early years of public charter schools, when lax authorizations and poor oversight allowed some terrible schools to open and stay in business. Today, the D.C. Public Charter School Board stands as a national model for accountability, while reforms in the public school system — matched with an investment of resources — have made it one of the fastest-improving urban districts in the country. The education system in Michigan, where Ms. DeVos worked for the expansion of charters and private school vouchers with little accounting for how students actually performed, suffers in comparison.

So there are lessons to be learned. Let’s hope Ms. DeVos is a quick study.