It's a well-documented and disturbing fact: African-American students are suspended from school at disproportionately higher rates than are their white peers.

And even though the overall suspension numbers have dropped in recent years, the racial disparities in school discipline continue to grow.

That troubling trend deserves more attention. Research shows that suspension does not reduce behavior problems or improve school safety.

Rather, kicking so many kids out of class can have harmful effects on the school environment and on the students themselves.

During a recent meeting, St. Paul school board members expressed frustration over the district's disproportionately high rates of black-student suspensions.

Though they make up about 30 percent of the district's enrollment, about 15 percent of all black students were suspended at least once last year, compared with 3 percent of white students.

And while suspension rates dropped steadily between 2006 and June 2010, they went up again during the past school year.

Anoka-Hennepin, Minneapolis other Minnesota districts and schools around the nation are struggling with the same issue.

According to a Minnesota Department of Education, the 52,652 suspensions during the 2009-10 school year translated into 110,033 missed days of instruction. About 40 percent of the suspended students statewide were black, although African-Americans make up only 10 percent of statewide enrollment.

National research says there is no evidence that black students engage in higher rates of misbehavior that other students. Yet minority kids are suspended more often, for less-serious and more-subjective behaviors, and with more-serious consequences.

The majority of the dismissals are for behaviors that don't threaten others -- only 2 percent involve a weapon.

The majority of offenses involve disruptive conduct or insubordination category, such as mouthing off, talking too much or too loudly, or challenging school staff. More than 2,500 suspensions were for absences, which only adds to the problem of poor attendance.

In too many cases, suspension only increases the already wide learning disparities between student groups. Sending kids home can lead to more suspensions, declining academic performance and a higher likelihood that they'll drop out.

It's important to keep struggling students in school but not simply send them to detention rooms or unsupervised study halls without instruction. School staff need to work with these students -- and sometimes their families -- to try to understand and change behaviors.

A proactive, preventative approach is required -- including more training for school staff and additional conflict resolution programs. The Positive Behavior Intervention Support (PBIS) program is being used with positive results in dozens of state schools and has been effective in other parts of the country.

A bill recently introduced in Congress would help fund preventative, research-driven approaches to discipline in U.S. schools.

Educators, families and communities should focus greater attention on keeping more kids in class. While tight school budgets make it challenging to devote more resources to a smaller group of students, it's an investment worth making.

Engaged students are dramatically less likely to become chronic truants, get involved in the juvenile-justice system -- or become adult offenders.

Investing in our young people at the first signs of trouble in school is more cost-effective -- and better for society -- than dealing with the costs of cops, courts, corrections and social services later.

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