Today is the anniversary of a historic event: the signing of the Civil Rights Act of 1964. It is hard to argue that America hasn’t come a long way. Measured by nearly every indicator, we have seen tremendous gains for blacks, as well as women and other racial and ethnic groups in this country. Many have benefited from a more equal playing field that created conditions to boost degree attainment, home ownership, and career opportunities. And, of course, we can’t forget to mention the nation’s first black president. It surely seemed unimaginable in 1964.

Some have said we are now a “post-racial” society, and I respectfully beg to differ. While there is much to celebrate, there is still much more to be done. Many of the gains we saw following the passage of the Civil Rights Act are quietly eroding: Chief among them is access to higher education, which we know is key to creating opportunities for students to reach their full potential. Barriers today are far more subtle than 50 years ago. There are no Klansmen to block the entrance to universities, but in their place are admissions policies that no longer consider race, while still giving preference to legacy applicants and children of university donors.

Even if we were to set aside the disastrous effects of “race-blind” admission policies at flagship public universities, there is the larger issue of what happens long before that. Far too many black and brown students still don’t have access to a high-quality, K-12 education, despite real progress in recent years. In states and districts across the country, children of color are less likely to have our strongest teachers. They’re also less likely to have access to rigorous courses that will prepare them for success after high school. And students of color — particularly black boys — are subject to harsh, exclusionary discipline at far higher rates than their peers.

These gaps in opportunity hobble the chances that black and brown students will move to the next level. More than 1 in 4 students of color, for example, do not graduate high school on time. The disparities between these students and their more affluent and white peers are undeniable.

This is not a post-racial society. We just don’t want to talk about it in terms of race. One has to be very brave to even bring up the subject. We are far more comfortable discussing poverty or social classes. But these topics are not proxies for race, and we will not do the tough work that remains 50 years past the passage of this law if we can’t begin with an honest discussion about race.

Although I was not alive on the day the bill was signed into law 50 years ago, as a black woman I have surely benefited from it. While that fact is perhaps unremarkable, it is stunning to consider that my own child and others of her generation will likely not benefit as much. In fact, statistically speaking, my mother — who was born in rural Mississippi in the 1940s to a single-parent domestic worker — had a better chance of social mobility than a child born today.

We cannot afford to continue moving backward on equity. It took real courage to pass the Civil Rights Act, but people weren’t afraid to be unpopular. Activists paid with their lives, and we saw real change. We need that same courageous spirit today, because the stakes are no less high and the battle for our children’s lives still begins with their access to a quality education.