Earlier this summer, we published a map of high school graduation rates by district across the United States. Were now breaking it down and exploring trends in different states and regions.

When you look at our national high school graduation rate map, it’s impossible to miss how low graduation rates are in the Deep South. These states don’t have the worst graduation rates in the country. That dubious distinction belongs to Oregon, New Mexico and Nevada.

But still, taken together, Southern states are a long stretch of low-performing districts, with very few bright spots. Alabama is the only state with any districts whose graduation rates are above 95 percent, and it’s only got six of them. (Most of those are small and hard to see. More on that in a moment.)

The abundance of green on the map — indicating a district with a graduation rate of 75 percent or lower — isn’t surprising when you consider that Louisiana, Mississippi, Alabama, Georgia and Florida all have statewide rates that low. So I changed the scale to see if any new patterns emerged:

Now, we can start to see some divisions between areas and important distinctions between the states. Let’s start with the not-so-good news. Mississippi and Florida both have more districts with a graduation rate below 60 percent than districts above 90 percent. In fact, Florida only has one district in the northeast corner of the state where 90 percent of students get their diploma within four years. So does Louisiana, along its border with Texas.

Among southern states, Alabama has the largest number of high-performing districts, particularly in its northern half. There’s also a curious pattern of city districts outperforming the surrounding larger counties. Let’s zoom in:

My first thought was that some of this might be explained by demographics. We know that fewer low-income students graduate high school than their wealthier peers. Maybe students in Alabama’s cities are more affluent, while county school districts have more poor students?

But here’s a look at the percentage of free and reduced-price lunch eligible students in each district compared with the graduation rate. In theory, the colors should match up somewhat. Districts with high-poverty populations should have low graduation rates and vice versa.

You can see that the northern cities do generally have fewer low-income students than the surrounding districts. But the comparison raises other questions. In the southern half of the state, home to most of the high-poverty districts, there are several examples of districts with the highest percentages of low-income students have above average graduation rates. What are these districts doing that is working well?

Much of the success can be chalked up to careful collaboration among staff, according to Molly Killingsworth, a regional support coordinator for the state. She works with Perry County Schools, where 93 percent of students were eligible for free or reduced-price lunch in 2013 and 87 percent graduated. Counselors monitor grades, teachers stay on top of interventions and administrators contact parents when needed.

“That should be occurring in all places, but sometimes it takes low numbers or high-poverty schools or something to shine a light to say, ‘This is what we’ve got to address,” Killingsworth said. “In the districts that have been successful, they have a finger on the kids.”

Keep checking back as we examine other regions of the United States in the weeks to come. Offer suggestions on places or trends you want to see covered in the comments or on Twitter: @sarahbutro or @hechingerreport.

[Cross-posted at The Hechinger Report]

Sarah Butrymowicz

Sarah Butrymowicz received a bachelor's degree from Tufts University and an M.S. from the Columbia University Graduate School of Journalism.