Marcia Chatelain is associate professor of history and African American studies at Georgetown University. She is the author of “South Side Girls: Growing up in the Great Migration.”

The statistics are startling: Black girls are disproportionately pushed out of school and into the criminal and juvenile justice system. Although they make up just 16 percent of America’s female student population, black girls account for more than one-third of all female arrests that take place on our school campuses, according to data from the Education Department’s office for civil rights. These young students are not only arrested but also frequently suspended or expelled from school, which often discourages them from pursuing a highly coveted tool for survival: an education.

Monique W. Morris, co-founder of the National Black Women’s Justice Institute, has spent years listening to the black girls behind the statistics and concludes that the arrests and detentions often worsen the social, educational and economic struggles of an already vulnerable group. “Black girls are being criminalized (and physically and mentally harmed) by beliefs, policies, and actions that degrade and marginalize both their learning and their humanity,” she writes in her book “Pushout.”

Schools begin pushing girls out at a young age; Morris documents arrests of girls misbehaving in kindergarten. Consider 6-year-old Salecia Johnson, who was arrested in Georgia in 2012 for a classroom disruption. Or 6-year-old Desre’e Watson, who was handcuffed and arrested in 2007 at her school in Florida after having a tantrum in class. These incidents and others for girls at older ages, Morris writes, “present a comprehensive, national portrait of how school responses to the disruptive behavior of Black girls push out and often render them vulnerable to further victimization and delinquency.”

Black girls suffer from a range of stereotyping that underlies officials’ reactions to their behavior. Racial biases influence school policies and determine the types of punishments inflicted, the book argues. “Black women and girls in America are subjected to dormant assumptions about their sexuality, their ‘anger,’ or their ‘attitude,’ ” Morris observes. “They have long understood that their way of engaging with the world — how they talk, how they walk, how they wear their hair or how they hold their bodies — is subject to scrutiny, especially by those in positions of relative power.” Researchers have found that black children are often misperceived as older than their actual ages, and the failure to recognize black girls as children has fueled the pushout problem.

"Pushout: The Criminalization of Black Girls in Schools" by Monique W. Morris (New Press)

Once a girl gets pushed out of school and into the criminal justice system, a host of troubles follow. Her educational advancement stumbles because, Morris says, juvenile detention is mostly focused on punishment. Many of the girls already are suffering from trauma, and an increase in surveillance and harsh treatment does not encourage academic performance. “Though many [juvenile detention facilities] operate with the intention or stated mission to be rehabilitative, the approach is often one that punishes children who have made mistakes,” Morris writes. “Today Black girls in juvenile correctional facilities have continued to endure hypersegregated and inferior learning conditions that prevent their full rehabilitation and fail to support their healthy development.”

The denigration of black girls in school and in detention is a symptom of a larger social ill that Morris encountered in her conversations with the girls. In one facility, she met a petite girl who introduced herself as Danisha. “I’m eleven years old,” she said. “And I’m a ho, that’s what I do.” Morris was saddened to hear her speak this way. “Danisha should have been telling us about her teachers or her fifth-grade homework,” Morris writes.

Danisha’s experiences of sexual abuse and exploitation are all too common among the girls Morris interviews at facilities across the country. “That exchange still haunts me,” Morris recalls, “mostly because since that day, I have encountered many more Danishas in and out of detention facilities — girls struggling to overcome the exploitative conditions of poverty and abuse.”

Morris proposes practical ways to stop the pushout of black girls. In an appendix titled Alternatives to Punishment, she reviews efforts to keep students in school rather than in institutional confinement. One approach currently implemented in 7,000 schools is called Positive Behavioral Intervention Systems, which aims to promote “prosocial behavior” as a way to cut down on disciplinary actions. “In New Hampshire,” Morris writes, “the implementation of the large-scale use of PBIS reduced suspensions (in-school and out-of-school), reduced office displine referrals [and] increased instructional time.” She observes that PBIS could prove beneficial for black girls who misbehave; the system helps students find ways to adjust their behavior rather than simply removing them from school.

As a survivor of childhood sexual assault, Morris says she is like many of the girls she interviewed and, like them, suffered trauma and participated in violence. “In many ways, I empathized with the girls who shared their narratives with me,” she writes. “What I learned and now know with certainty from this experience is that education of Black girls is a lifesaving act of social justice.”

“Pushout” is for everyone who cares about children, especially teachers, school administrators and policymakers, whose decisions — big and small — shape how black girls learn and live.

The Criminalization of Black Girls in Schools

By Monique W. Morris

New Press. 277 pp. $26.95