Following President Obama’s call for free community college, there has been much discussion of the role of community colleges in increasing access to college and improving our society. Predictably, opponents of the president’s proposal have pointed to low completion rates to support the claim that community colleges are a lost cause.

The facts don’t support the conclusion. Compared to other institutions of higher education, community colleges disproportionately serve socioeconomically vulnerable and underprepared students. If you focus on graduation rates for this population, community colleges end up looking pretty much like four-year colleges. Claims that for-profits do better with the same population are based on misleading statistics and false comparisons.

So attacks on community colleges should stop. At the same time, no one—least of all community college leaders—is satisfied with the outcomes for students who enroll in community colleges. The great majority of community college students do not achieve the goals with which they started their post-secondary education. That is not the fault of community colleges, and it’s not the fault of their students, many of whom were handed inadequate opportunities for education before getting to college.

So instead of blaming community colleges, perhaps we can help them succeed.

Three years ago, with support from the Bill and Melinda Gates Foundation, Campus Compact took up that challenge. We built a model called Connect2Complete—C2C—that integrates service learning and peer advocacy into developmental education courses in two-year colleges.

Developmental education courses are non-credit-bearing courses taken by students entering community college to prepare them for college level work. Students who start their college careers in developmental education face long odds for completion. They are also disproportionately low-income, students of color, and first-generation. So if we want a future of shared prosperity, we have to improve outcomes for developmental education students.

We piloted C2C in three states: Florida, Ohio, and Washington. Supported by national and state Compacts, college staff and faculty in each state integrated the model into their developmental education curricula.

A team of researchers at the Heller School for Social Policy and Management at Brandeis University evaluated the outcomes. Here was their key finding: When institutions implemented the model with fidelity, persistence among C2C participants was higher than a comparison group of developmental education students not in C2C. After six semesters, the persistence rate among C2C students was six percentage points higher than among non-C2C students. For those of you who have not participated in endless discussions of retention on college campuses, a six percentage point gain is an enormous increase.

Why does C2C work? Based on surveys and qualitative evidence gathered by the evaluators, there seem to be two categories of answers. C2C helps students build strong relationships with faculty and with peers. And C2C helps students understand themselves as people who can make a difference in the world.

Campus Compact is finalizing tools to help campuses implement the model. We will be publishing a print manual, the first run of which will be available free. That manual and additional materials will also be available free on our website. If you are interested, you can see the evaluation report and sign up to receive a free copy of the manual here.

All of the usual disclaimers apply: This was a pilot study. More research needs to be done. Hypotheses about causal factors are speculative. In that spirit, we invite community colleges and education associations to borrow the model, implement it, and rigorously evaluate the outcomes. We need to know more about what will advance community college students along a pathway toward completion.

The nature of politics in the United States in 2015 means that community colleges will now become a political football. Opponents of the president will denounce them. Supporters will embrace them. But community colleges are too important to our future to be reduced to a talking point. Those of us who care about equality and prosperity must focus on how to help community colleges—and the students who choose them—succeed.