Thousands of elementary students were suspended from public schools last year in Washington and its suburbs, some of them so young that they were learning about out-of-school discipline before they could spell or multiply.

Those sent home for their behavior included kindergartners in nearly every area school system — 94 in Prince George’s County, 74 in Fairfax County, 61 in Anne Arundel County, 50 in the D.C. school system, 38 in Prince William County and 22 in Montgomery County.

They included children who idled at home for a day or two and some who accompanied their parents to work.

They included the pre-kindergarten son of Rajuawn Thompkins, who said the boy was removed from his D.C. charter school for kicking off his shoes and crying in frustration. Thompkins had thought the boy was too young to be suspended.

He was 4.

“I would explain it to him, and he still didn’t understand,” she said. “He’d ask me, ‘Mommy, why can’t I go to school?’ ”

His pointed question underlies a debate about the merits of out-of-school suspension.

Some researchers and critics question whether children in the early grades should ever be suspended. The goal should be teaching appropriate behavior, they say, not sending students home.

Still, many educators see suspension as necessary — a strong message about conduct that crosses the line. Many parents, too, suggest that students who cause a disruption in class, no matter what age, need to be removed. Especially when a child or teacher has been physically hurt, many principals view suspension as an important tool.

A Washington Post analysis of data for 13 of the region’s school systems found that last school year more than 6,112 elementary students, from pre-kindergarten through grade 5, were suspended or expelled for hitting, disrupting, disrespecting, fighting and other offenses.

The total includes 433 kindergartners, 677 first-graders, 813 second-graders and 1,086 third-graders. More than 50 pre-kindergartners were suspended.

In all, those cases represent a small segment of suspensions in the region, and affect from 1 percent to 3 percent of elementary children in most school systems. But some experts say that age sets them apart.

For children younger than 7 or 8, “all they understand a couple of days into this is they are having snow days — and nobody else is,” said Walter S. Gilliam, author of a national study on pre-kindergarten expulsions and director of the Edward Zigler Center in Child Development and Social Policy at the Yale Child Study Center.

Gilliam said suspension is at odds with teaching the social and behavioral skills many young students lack. “We would never send a child home because that child was struggling at reading,” he said. “We would never send a child home if that child was struggling with math. Why would we send a child home for struggling with social-emotional skills?”

On those removed from school, the effect is complex. They lose instruction time and slip behind in classes. But there may be other fallout, too: lower regard from peers or teachers, a shift in identity, an alienation from school. “I would be worried it would set in motion a negative trajectory that would gather momentum across the next years of schooling,” said Anne Gregory, a Rutgers University assistant professor and education researcher.

School officials said they try to avoid suspensions of the very young and use positive-behavior initiatives to prevent discipline problems. They said that relatively few students are suspended and that those cases often involve safety issues or repeated misbehavior.

“To me a suspension is for something so unprovoked, or something so out of the norm, that I, as the adult, had no other option,” said Judy Brubaker, principal at Spark M. Matsunaga Elementary School in Germantown.

Brubaker and other principals said they carefully consider each case and often look to other options — involving parents and counselors, creating behavior plans — before suspension.

It is “absolutely not our default,” said Kimberly Willison, principal of Clearview Elementary School in Herndon, who recalled several cases, each with escalated circumstances. “It’s not something we ever do lightly,” she said.

In Alexandria, Lawrence Jointer, director of hearings, investigations and student alternative services, said discipline problems appear to have intensified during his career of four decades. “We see aggressive behavior from kindergarten on up,” he said, and it is tough to affect that behavior when parents are disengaged.

“I understand it gets to a point where principals and teachers feel they’ve tried everything they can,” he said. Sometimes, suspension is a way to “drive the point home: ‘This is serious behavior we’re dealing with at school, and we need your support.’ ”

Nationally, suspension practices are being debated and rethought. The Maryland State Board of Education is considering proposals to end suspensions for nonviolent offenses. Last summer, federal officials launched a broader discipline reform effort as new research highlighted harmful effects.

Many experts say no research indicates that suspensions improve a child’s behavior or make schools safer. But studies have shown that suspended students are more prone to low achievement, dropping out of school and landing in the juvenile justice system.

In elementary school, behavior problems can be rooted in academic gaps — being unable to read, for example, when classmates are poring over books, said Sara Rimm-Kaufman, associate professor of education at University of Virginia. “It’s an emotional response to not knowing what everyone else knows,” she said.

Suspensions have markedly increased nationwide since the 1970s, and some experts suggest that suspensions of younger children reflect, in part, a zero-tolerance culture that has taken hold in schools during the past 20 years.

Among cases that attracted national attention was the 2010 suspension of a Michigan 6-year-old who formed his hand into the shape of a gun. A year earlier, a Delaware 6-year-old was ousted for having a Cub Scout camping tool that included a knife.

Last spring, an 8-year-old boy in Fairfax pocketed a pill for his attention deficit disorder as he rushed to leave for school. After he went to take the medication during a restroom break, he was suspended for possession of a controlled substance, his mother said.

Fairfax, which was under fire at the time for its discipline policies, has since eased its approach to prescription medication, allowing principals more discretion in punishment. The 8-year-old was out of class for 10 school days, his mother said. “It was extreme,” she said.

Fairfax School Board member Elizabeth Schultz (Springfield) said the key to suspension is “proportionality.” Some families have complained about elementary-age students suspended for disrupting class and going to the bathroom repeatedly, she said. “To me, it has to be really significant,” she said, such as imminent danger.

Psychologists and researchers say suspensions can send the wrong message.

“At that age, most of them go home, and if they are allowed to watch TV or play video games, it can be more fun than school and reinforce the behavior that is negative,” said school psychologist Melissa Reeves, who teaches at Winthrop University in South Carolina.

Some schools, Reeves said, rely on suspension because they lack funding for other options. “The challenge,” she said, “is having the resources for alternatives,” programs that teach anger management, social skills, problem-solving and conflict resolution.

In Prince George’s, A. Duane Arbogast , chief academic officer for county schools, said suspension is one of many tools to improve student conduct. Sometimes, it is also needed to set a tone in a school or to be responsive to victims. “It should be used tactically and strategically,” he said.

Arbogast said the 94 kindergartners suspended in Prince George’s last year represent a small share of those enrolled. “About 1 percent,” he said. “. . .Ten percent would be crazy. One percent does not surprise me.”

In Arlington County, Assistant Superintendent Meg Tuccillo said that elementary-age suspensions are rare — 13 last year across 22 schools — but that one might occur when, for example, “a youngster has significantly hurt another youngster.” She added: “Sometimes, either we need time to develop a plan or we need a breathing period.”

Advocates and parents say behavior problems are sometimes signs of undiagnosed disabilities. A second-grader with autistic-like behaviors, prone to meltdowns, was suspended for more than 10 days of kindergarten in Prince George’s, his mother said, and several days of first grade. Now in second grade, the child has qualified for special education services, but he already has lost nine days to suspension and informal send-homes, his mother said.

“It was like he was being suspended for his disability,” she said.

In general, the school system is cautious about such designations, said Arbogast, the academic chief. “You don’t want to necessarily put a label on a kid at age 5,” he said.

How many of the young fully grasp their punishment is hard to know.

“Some can understand the conversation, but others are looking at me, kind of smiling, like, ‘What is all this about?’ ” said Jointer, of Alexandria, who presides over serious suspension cases and every so often sees a kindergartner or first grader.

Teachers describe classroom difficulties with some children lacking basic social skills, said Tim Mennuti, president of the Teachers Association of Anne Arundel County.

In the District, Judith Sandalow, executive director of the Children’s Law Center, said recent suspension cases include a kindergartner who pulled a fire alarm, a second-grader with multiple suspensions for fighting, and a third-grader accused of sexually harassing an aide.

“It is never the right answer to suspend an elementary-age child,” she said.

In young children, particularly, she said, misbehavior is a sign of something deeper — family problems, learning disabilities, academic gaps. “It is a sign they are experiencing something in their lives, and they should be helped,” she said.

For parents, suspensions have ripple effects.

Thompkins, whose pre-kindergartner was suspended from Imagine Hope Community Charter School, missed work when her son was suspended and when he was less formally sent home early. “He was suspended so often I lost my job,” she said.

Several calls to the charter school for comment were not returned.

D.C. Public Charter School Board member Darren Woodruff said that charter schools have their own disciplinary practices but that suspensions in the early grades may be an issue to examine. “We support best practices and research-based practices,” he said.

A majority of Washington area school systems suspended at least one pre-kindergartner last year, the data show.

Last year, The Post profiled a pre-kindergarten case in Arlington in which a 3-year-old in a public Montessori program was removed for having too many potty accidents. Arlington officials said that the child was not suspended but that the family was asked to work on toilet skills at home for a period.

In Prince William, Todd Erickson, associate superintendent for central elementary schools, said he finds the suspension totals “rather small,” which “shows us we’re doing a good job with the other students.” He cited anti-bullying and positive-behavior efforts.

Brian Butler, a veteran Fairfax principal, said the goal of elementary-level discipline is “a teachable moment for the child.”

Age is a factor, he said. “If I had a kindergartner who hit somebody,” he said, “I would call the parents.”

Staff writer David Fallis contributed to this report.

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