The number of students suspended from Minnesota schools has dropped by about 20 percent since 2010, a sizable decline as educators have tried to find new ways to deal with unruly students.

New data by state education officials released Thursday showed the number of black students suspended from Minnesota schools dropped by 26 percent over the same period.

But a deeper look shows that the number of black students who received more serious suspensions, of one day or more out of school, declined only 9 percent statewide since 2010. Black students accounted for 40 percent of all suspensions of a day or more in 2014, up from 38 percent in 2010, even though they make up less than 10 percent of the student population.

"The gap on suspensions hasn't narrowed, and that continues to be a problem," said Sue Budd, with ­ISAIAH, a Minnesota group of clergy members who have called for moratoriums on suspensions for students of color.

Overall, suspensions of one day or more have dropped by 13 percent statewide since 2010. Suspensions of any kind — whether it was a one-hour trip to the principal's office or a one-day suspension — dropped by 20 percent for the same time period.

Minnesota Education Commissioner Brenda Cassellius credited the decrease in suspensions primarily to schools' use of Positive Behavioral Intervention Services, which provides training to school staff members to help them deal with students with challenging behavior.

Since its launch in 2005, the training has been implemented in roughly 25 percent of the state's schools. Gov. Mark Dayton's 2015 budget calls for spending $4.6 million to add 600 more schools.

On Thursday, Cassellius met with local education leaders for a roundtable discussion about how the training has affected student behavior.

"These schools understand that suspensions are not an effective measure of discipline, and often cause a child to fall behind in class," Cassellius said.

Many of them agreed that getting teachers, principals and support staff to communicate better was having a dramatic impact on student behavior.

"It's a big shift in thinking," said John Beach, principal of North Elementary in Prince­ton. "We are creating an environment for our students to succeed."

Cassellius said schools have to work harder to ensure there's no disparity between how students of color and white students are punished.

Federal civil rights officials in the U.S. Department of Education in 2013 launched an investigation into Minneapolis Public Schools' suspension policies after they audited records for 11 district schools. This fall, Minneapolis Public Schools announced it would change its policy to require a review of all suspensions of students of color. It also banned suspensions of students in prekindergarten through first grade.

The announcement followed a report in the Star Tribune that showed black students were 10 times more likely to be sent home than white students.

St. Paul schools have made it a priority to reduce suspension rates and were seeing gains before a difficult 2013-14 school year when sixth-graders were shifted to the middle schools and students with emotional and behavioral disorders were moved into regular classrooms.

Suspensions for students in the grades 6-8 middle schools jumped 63 percent — 141 percent for sixth-graders alone.

Disruptive behavior continued into the fall at Ramsey Middle School, prompting the district to deploy new student support teams that include behavior specialists who monitor hallways between classes and meet with students. Two security officers were hired.

At a meeting Thursday night at Ramsey, about 50 people — many of them parents — listened as Principal Teresa Viber pointed to early signs of an improved school climate. Discipline referrals, she said, were down from an average of nearly 30 per day in December to 13 per day in February.

Staff writer Anthony Lonetree contributed to this report.