Speaking at Boston’s Institute of Contemporary Art on Tuesday, U.S. Education Secretary John B. King Jr. said teachers need more flexibility to adequately prepare all students for college and careers.

“Massachusetts, despite incredible progress over the past few decades, still has a 30 to 40-point achievement gap for African-American and Latino students. That’s a gap we have to close,” King said at an event hosted by Empower Schools, a non-profit that partners with cities and towns to help them improve their schools.

King used to run a charter school in Boston's Roxbury neighborhood and he urged state lawmakers to think of a better way to combine the autonomy of charter schools with the accountability of traditional public schools.

“I think the challenge is making sure both the autonomy is real and the accountability is real. And as you look across the country, you see places where there is foe autonomy and you also see foe accountability,” King said.

Today, there are 81 charter schools in Massachusetts. In November, Massachusetts voters will consider a ballot question that would substantially increase those numbers.

NPR Ed: How Massachusetts Schools Went From The Middle Of The Pack To First Place