In recent decades, access to a college education has expanded tremendously across the United States. But with college completion rates hovering at about 50 percent, and American businesses facing a shortage of educated workers, our nation is realizing that the ultimate goal is not college entry but college completion. That is why President Obama set a national goal for the United States to increase the percentage of citizens with a degree from 40 to 60 percent over the next decade.

It’s time to set the same finish line for D.C. children. While Washington has one of the most highly educated workforces in the country, children attending D.C. Public Schools (DCPS) are among the least likely to attain the thing most likely to lift them out of poverty: a college degree.

The good news is that, over the past decade, two efforts have significantly expanded college access for D.C. high school graduates. The D.C. College Access Program has placed advisers in high schools to teach students how to apply and pay for college. And D.C. Tuition Assistance Grants (TAGs) have provided scholarships to help students attend out-of-state public, local private and historically black colleges and universities.

Unfortunately, inadequate attention has been paid to whether D.C. students complete their degrees and which colleges give them the best chance of doing so. On that front, the news is not so good.

The D.C. government recently released data on the first five years of the TAG program, including college graduation rates for 80 percent of TAG recipients. Importantly, TAG grants allowed those 5,000 students to attend institutions that have, on average, graduation rates of 60 percent — above the national average. Yet, only 1,900 of those students, or 38 percent, graduated, far below the national average.

Part of the reason: Most DCPS graduates are not ready for college. Notwithstanding progress in recent years, DCPS still ranks at or near the bottom of metropolitan school systems in student achievement. Not surprisingly, research shows that students who enter college underprepared are less likely than others to earn degrees.

But inadequate preparation is far from the whole story. Where D.C. students go to college also matters tremendously. Consider two historically black universities that have achieved radically different results even though their student bodies have almost identical SAT averages and percentages of poor and African American students. Of the 45 TAG recipients who went to Coppin State University in Baltimore, only four graduated within six years. Compare that 9 percent graduation rate to the 36 percent at North Carolina Central University, where 73 of the 190 TAG recipients graduated within six years. Students with higher SAT scores attending one of those two colleges could perhaps have attended Howard University, where 60 percent of entering TAG recipients ultimately graduate.

Such divergent results send a clear message: The District cannot send kids off to college and turn a blind eye to what happens next. Three key levers (among others) could help D.C. improve college graduation rates:

l Ensure that increasing numbers of students are college ready. The District has committed to implementing a rigorous college-ready core curriculum, a good first step. The city can build on that by assessing college readiness early in high school, using the actual exam that colleges use to place students in remedial education, and then implement strong programs during the final years of high school to close identified gaps.

l Advise students not just on how to apply and pay for college, but where to go. There is simply no excuse for advising a student to attend a college where they have a 9 percent chance of succeeding when there is another option with four times (or higher) the graduation rate that suits the student’s financial situation, academic record and career goals.

l Collect and fully utilize student outcome information. The District should do a better job of benchmarking data on the number of students — DCPS and charter school graduates — who enter college, who need remediation and who earn degrees from different colleges in what period of time.

To match the aspirations of students and the needs of families, the commitment to college access must continue. After all, students cannot complete college degrees if they never have a chance to enter college. That is why Congress should reauthorize the Tuition Assistance Grant Program when it is up for consideration next year.

But committing to access alone will not enable D.C. students to succeed. College graduation must become the true measure of success.

The writer is executive director of the College Excellence Program at the Aspen Institute.