The high school graduation rate in the U.S. reached an all-time high of 83 percent in the 2014-2015 school year, President Obama announced today, marking the fifth straight record-setting year.

Achievement gaps have narrowed even as all boats have risen. Graduation rates range from 90 percent for students who identify as Asian/Pacific Islanders to 64 percent for students with disabilities.

In remarks at Benjamin Banneker Academic High School in Washington, D.C., the president used the good-news announcement as an opportunity to tout his education initiatives, from Preschool for All through the America's College Promise free community college partnership.

"When I took office almost eight years ago, we knew that our education system was falling short," he said. "I said, by 2020 I want us to be No. 1 across the board, so we got to work making real changes to improve the chances for all of our young people ... And the good news is that we've made real progress."

High school graduation rates in the nation's capital, he noted, have grown faster than anywhere else in the country, from 53 percent to 69 percent.

While the graduation rate continues to climb, the improvement comes at a time when the scores of high school students on the test known as the "Nation's Report Card," are essentially flat, and average scores on the ACT and SAT are down.

As we've reported, the rising graduation rate reflects genuine progress, such as closing high schools termed "dropout factories," but also questionable strategies by states and localities to increase their numbers.

"For many students, a high school diploma is not a passport to opportunity, it's a ticket to nowhere," says Michael Cohen, president of Achieve, a national nonprofit that's long advocated for higher standards and graduation requirements.

Cohen points out that roughly half of states now offer multiple diplomas. Some of those credentials are rigorous, some aren't. "You don't know how many students who were in that graduation rate actually completed a rigorous course of study. We're not transparent about that. We're concealing a problem."

In many places, the high school graduation exam is also a low bar, Cohen says, while some states have dropped it altogether.

Just last month, in a major school funding ruling, Connecticut Superior Court Judge Thomas Moukawsher excoriated his state for watered down graduation standards that, he says, have already resulted "in unready children being sent to high school, handed degrees, and left, if they can scrape together the money, to buy basic skills at a community college."

It's difficult to know which states earned this uptick in graduation rates through high standards and hard work and which states achieved it through shortcuts and lowered expectations. In some cases, it's all of the above.

Trends vary widely from state to state. Ohio's graduation rate has been flat, while Georgia's reported rate has risen more than 10 points, from 67 percent to 79 percent since 2010-2011. It jumped more than six points from last spring to this spring.

According to the Atlanta Journal-Constitution, Georgia officials credited the rise to an increased focus on attendance and dropout prevention as well as to the elimination of state exit exams. But school employees in Atlanta have also reported pressure to inflate grades, particularly for students enrolled in online "credit recovery," which allows students to make up failed courses.

See below for more of our reporting on the graduation rate.

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