Massachusetts enjoys a history as an educational leader dating to the early days of our country. The 1993 Education Reform Act positioned Massachusetts at the forefront of school reform and produced gains in student learning that are the envy of every other state. Now, the Obama administration's Race to the Top program gives Massachusetts another chance to lead, this time by fully integrating public charter schools into the fabric of the commonwealth's education system.

Charter schools are public schools open to all students. They're accountable for their performance and overseen by the state, which has closed down lower performing charters even when these schools outperformed nearby traditional public schools. But unlike traditional public schools, charters have autonomy and flexibility. For example, they can reward their best teachers and fire low performers. This autonomy—not the red herring of funding—is why charter schools are so contentious.

Across the country the experience with charter schools is mixed. Charter schooling is producing amazing schools, many among the best in America. At the same time, the openness of the charter sector is also creating some quality problems. Charter quality varies state by state and owes a great deal to different state polices.

In Massachusetts, however, the evidence is more conclusive. Although quality is not uniformly high, a study earlier this year by a team of researchers from Harvard, MIT, and Duke found that in Boston "charter schools outperform all other schooling options there, including the city's pilot schools." Schools like MATCH and Roxbury Prepare are national models, and outstanding charters can be found throughout the commonwealth. In 2009, six of the ten highest performing high schools on the language arts MCAS test were public charter schools, as were the three top performing high schools in math.

Students whom many believed could not achieve at high levels are succeeding in Massachusetts charter schools. Despite Massachusetts reforms, too many students, especially students of color, still struggle in traditional public schools. Charters are helping serve these students. For instance, more than 60 percent of charter school students in Boston are black, compared with 37 percent in the city overall.

More important than test scores is that charters provide differentiation within public education. In Massachusetts and elsewhere there is resistance to standards because one size does not fit all. In practice it is our educational delivery system, essentially a singular model of schooling, that drives homogeneity in the system. Charters introduce much-needed customization, dynamism, and innovation without eroding standards.

Yet Massachusetts caps the number of charter schools that can open. As in other states with caps, this is an accommodation to various special-interest groups that see charters as a threat. But it makes no sense to cap the growth of charters, especially not the very best ones. U.S. Education Secretary Arne Duncan has made his opposition to caps clear, and strong charter-school policies will comprise almost 10 percent of the points states receive in the Race to the Top competition.

Ideally, states should forgo caps and instead rely on high-quality charter-school authorizers to make decisions about who can open charter schools and to provide ongoing oversight of existing charters. After almost two decades of national experience, the elements of effective charter-school authorizing are not a mystery. Today the National Association of Charter School Authorizers can offer states evidence-based model policy.

Short of lifting the cap altogether, policymakers can ensure that high-performing charter schools can replicate. In December, Michigan passed legislation creating a smart charter cap letting proven schools open additional schools. That legislation provides the seeds for a compromise in the charter-school debate in Massachusetts. With a smart cap, there is no question about whether the charter schools being enabled are a risky proposition, because they are linked to proven schools.

Opening up American public schools to more choice and competition is contentious. Choice, by itself, is not synonymous with better educational outcomes. However, Massachusetts can build on its charter success and use charter schools to improve its education system. By doing so now, Massachusetts can claim a spot at the front of the Race to the Top. The policy options are apparent; the only thing standing in the way is politics.