Externalities in the Classroom: How Children Exposed to Domestic Violence Affect Everyone’s Kids

Many teachers believe that a “few bad apples” can spoil a whole classroom, reducing the learning of everyone in the room. While this is part of the folk wisdom of teaching, it has been surprisingly difficult to find these effects in the data.

But a very convincing new paper, by Scott Carrell of U.C. Davis and Mark Hoekstra of U.Pitt, “Externalities in the Classroom: How Children Exposed to Domestic Violence Affect Everyone’s Kids” (available here), suggests that these effects can be pretty big.

The real difficulty in this style of research is to find a useful proxy for whether or not a classroom is affected by a disruptive student. Previously researchers have used indicators like whether a student has low standardized test scores, but as any teacher knows, the under-performing kids may not be the disruptive ones. And if you analyze only a weak statistical proxy for classroom disruption, you get weak estimates, even when the true effects are large.

The truly innovative part of the Carrell and Hoekstra study begins with their search for potentially disruptive kids: they looked for those coming from particularly difficult family situations. In particular, they combed through court records and linked every domestic violence charge in Alachua County, Florida to the county schooling records of kids living in those households.

It’s a sad story: nearly 5 percent of the kids in their sample could be linked to a household with a reported domestic violence incident. (And given under-reporting, the true number may be much larger.)

The costs of this dysfunction are even more profound. Kids exposed to domestic violence definitely do have lower reading and math scores and greater disciplinary problems. But the effects of this dysfunction are not limited to the direct victims of this violence: kids exposed to kids exposed to domestic violence also have lower test scores and more disciplinary infractions.

Around 70 percent of the classes in their sample have at least one kid exposed to domestic violence. The authors compare the outcomes of that kid’s classmates with their counterparts in the same school and the same grade in a previous or subsequent year — when there were no kids exposed to family violence — finding large negative effects.

Adding even more credibility to their estimates, they show that when a kid shares a classroom with a victim of family violence, she or he will tend to under-perform relative to a sibling who attended the same school but whose classroom had fewer kids exposed to violence. These comparisons underline the fact that the authors are isolating the causal effects of being in a classroom with a potentially disruptive kid, and not some broader socio-economic pattern linking test scores and the amount of family violence in the community.

You likely already believe there is an equity rationale for trying to help those kids subject to difficult family situations. This research also suggests a compelling efficiency rationale, as the effects radiate well beyond the dysfunctional household.

Pierre-Louis Morel

@35 The study doesn't mention the family income of the violent family (it only mention that rich white boys results are more affected, and that the behavior of poor white boy and poor black girls are affected).

The only data I can give on violence and income/situation is in french, and specific to Paris, rather light on details though that's the only one I have on hand http://www.paris.fr/portail/viewmultimediadocument?multimediadocument-id=35557

The violences (to women) aren't tied to household income but to the personal situation of the wife (student, no work). With anecdotal evidence that the upper echelon might be under-reported (instead the women being put in asylum).

So the violence are more likely tied to power than household income (kinda like sexual harassment, with the male/female proportion of victims relating to the female/male proportion of those in situation of power).

Princess Leia

Extremely interesting post and comments.

Mr. Dokes sounds like a great teacher: He goes straight to the heart of the matter, gets people thinking about a tough topic, and is not easily offended. :)

In fact, administrators and colleagues probably try to load his classroom with certain students (aka jerks) out of respect for the fact that he is an effective teacher.

jim gundlach

This is a very innovative and IMPORTANT study. The main implication of this is that the guy down the street who beats his wife and who has a kid who is your kids classmate is causing your kid to get less from her education and increasing the chances that she will misbehave at school. And the root cause is domestic violence, not bad kids or "jerks".

I might add that the differences found in this study underestimates the actual effects because there is obviously some domestic violence going on in the homes of the kids the study classifies as not domestic violent. That means the comparisons include groups of scores are somewhat lowered and disruptive behavior somewhat elevated than it would be if you could eliminate all domestic violence effects. In other words, the reality is that measurement error is reducing the measures of the extent of the problem in this study, or more simply this is a bigger problem than the researchers report.

One final note is that I am appalled with the number of people who will simply label these kids bad or jerks and simply dispose of them. They are human beings, not responsible for their situation, and they will be part of us for a long time. Just throwing them out only moves the problem elsewhere and makes it worse.


E. Kuhn-Osius

There are a number of things that the study does not say, it seems, but nonetheless it serves at least one very useful function. The study does not really tell us what to do with children who come from abusive situations. The study also does not establish that all problem children come from abusive situations. There may be others, and some children with terrible homes may not have problems at school. The only thing that the study makes very clear is that 'problem children' (in this case, children with problems at home) do have a negative influence on the learning of others and that something beyond the traditional measures need to be taken if we want to avoid that negative consequence. If the statistics hold up, it is no longer possible to just attribute the problems solely to the (in)competence of a specific teacher, which is what happens all too often and what was about to happen to the teacher who called some students jerks. No matter what he may call them and how much others may like what he calls them, the problem cannot be solved by just one teacher alone and evidently also not by the counseling apparatus that is in place. And this is what the study shows. It is probably not something that an experienced teacher would not know, but now some others may begin to believe what many experienced teachers have been trying to tell unbelieving and unhelpful parents and administrators.

While I share fears with people who are afraid that such a study may lead to abandonment/segregation of problem children, I also think that more consideration needs to be given how to handle seriously uncooperative students. They can be a serious problem all the way into college teaching when students are less easily distracted and the teacher doesn't have as much of a responsibility to keep a young adult in a teaching situation in which he [usually] doesn't want to be.



I've been a h.s. teacher in L.A. and NYC for over a decade, and the #1 cause of student under-achievement is what I & others have called, as an umbrella term, "toxic environments." This includes exposure to domestic violence at home, but also includes:

*exposure to violence in their communities,

*exposure to substance abuse (in utero, at home, and/or in the community),

*family dislocation (foster care, having to move constantly, moving between homes within the family, etc),

*employment trauma (unemployment, underemployment, over-employment i.e. caregivers having to work multiple jobs to stay afloat, caregivers working nights/weekends leaving students to fend for themselves, and students having to work nights/weekends to help the family), and

*outsized family responsibilities (students having primary or predominant child care duties for younger siblings, or students who serve as primary caregivers for sick/injured/drug-abusive adults, or students who serve as translators for adults due to adults' lack of English skills)

...any number of these factors in students' lives often leads to difficulty in the classroom, based on skill deficits or emotional deficits.

All commentators here should take note that POVERTY is at the core of most of these toxic issues. I bet that young people are several times more likely to recover from emotional trauma at home if their family has some economic foundation.


1) social/mental/emotional care at school. My school in NYC had extensive social care available for the so-called "jerks," in individual and group settings, and over time, that extra out-of-classroom support paid enormous dividends in terms of behavior modification and academic improvement. Without funding for that care at my current school in L.A. this past year, several students' behaviors (and grades) spiraled out of control.

2) rigorous, relevant and college-preparatory curricula school-wide. Getting students out of the cycle of poverty, via higher education, is the #1 goal over the long term. Poverty breeds the desperation and dislocation that makes exposure to domestic violence (and all the other toxic factors mentioned above) all the more common.


Amanda Cheetham

If you're a teacher, this article says nothing new. I have taught high school for the past 7 years in a low-performing school. I love my job and I love my students as if they were my own kids. The first guy, Dokes, should not be put down for calling a kid a jerk. Whether the student is a product of DV is not always the case. There are also some kids who are straight up malicious.

Do you NON-TEACHERS know how many "bad apples" cheapen the rich academic environment that so many teachers spend months to create? Class cannot move on because of ONE STUDENT. I feel so sorry for the students who are in the classes w/ students like this.

To cure this, schools have the "detention" room w/ a football coach or someone scary ruling the room for the period. But all the kids do is goof-off and get out of class. What to do?


I think the study also suggests that people are wrong when they say problem children could use a "strong hand" at home -- usually meaning that they could use some corporal punishment. Battering husbands and fathers make for out-of-control kids who bully others, not well-behaved, disciplined children.


We need to look systemically at where we are spending our dollars-which seems to be intervention, not prevention. Funding a home visitation program for the first year of a newborn's life saves between $6,200 and $17,000 per youth, increases tax revenues while decreasing costs within the education, social service and criminal justice systems. It decreases child abuse and neglect, reduces subsequent pregnancies and increases labor force participation by parents and family income.

Furthermore, we need a much more robust safety net for subsequently at-risk families. Let's talk about the role of Child Protective Services, state agencies which we KNOW are grossly underfunded. We are all disgusted and horrified when we hear of foster children who died 5 years ago and the social worker still didn't know. But are we intervening to change the funding to reflect a cost-benefit analysis? I would hope the study reported here would affect CPS funding. We need to think systemically.



Mike wrote above:
"There's reaching out to help a troubled student, and there's holding back the whole class due to the minority of students in the classroom that is formed by these troubled students. If only we had as many parents concerned about the lack of reaching out towards the gifted students as we do towards the troubled ones."

Mike et al misunderstand the situation being described in the research. As a kid in Brooklyn, I was very aware that some of my classmates acted as if violence was always a possible solution in almost any situation. A teacher reaching out to me was good. But it could be no protection from kids who had learned to use violence -- teachers can't be omnipresent. Kids learned from other kids. That's where I learned violence, carefully timed to be away from the view of teachers, can get you what you want.


"I hope my boys are taught by teachers who work to reach even the most troubled kids in the class and who jump at teh chance for more information and understanding about the social stresses the students and their families face."

That sounds good on paper, but you'd sing a different tune if you realized that that teacher is in fact spending all their time managing the troubled kids and not actually teaching. That's when the whole classroom breaks down.

I've seen it happen in my child's classroom with just a single disruptive kid. This child managed to collect a gaggle of toadies around him and his presence in the classroom effectively shut it down.

Several months into the year another parent discovered that his parents had actually moved out of the city and were transporting him to school every day illegally. Because he was bullying his child, he "dropped a dime" on him and he was gone within a week. The classroom transformed overnight.



Does this account for the division of students on up the ladder? My school system always had remedial, general, college prep, and honors/AP classes. I get the feeling the correlation with domestic abuse children's classmates could just be a result of those children being in general classes.


@22, I would rather have counselors on campus who could counsel instead of do paperwork, a home-school liaison to focus solely on parent/teacher communication, and a social worker who knows the ins and outs of governmental policy regarding these situations. These key figures in low-income/generational poverty schools like mine could help make a determination along with me as to what is good for a child. Most of my kids have some issue with their home lives -- if I could make it happen, they'd all be in counseling.

I do like the idea of using NCLB money for such a program, but the program is already underfunded by the federal government. Common-sense solutions like yours tend to fall on deaf ears the higher one goes in educational bureaucracy, especially in this political climate. I think the state government might handle such an idea better.


I think the largest problem with the study is that it requires a domestic violence charge actually happen (I would say by methodological necessity). While more completely measurable, it leaves out a large chunk of the population that doesn't file charges against their perpetrators. I am wondering how the children of those domestic violence recipients act compared to the children of those who actually filed. I wonder if those children wouldn't be the quieter ones or the ones who attempt to act normally. With those children, the cost to the school might also be the cost of providing counseling to these children.


You say, "It's a sad story: nearly 5 percent of the kids in their sample could be linked to a household with a reported domestic violence incident. (And given under-reporting, the true number may be much larger.)" and I don't doubt that some incidents of domestic violence go unreported. However, it's also true that 5 out of 6 DV reports in the context of a divorce proceeding are ultimately judged to be unfounded which is gross overreporting. How do you detangle those two effects? The problem, I think, is in tying to "reported" domestic violence and not actual violence.


Thank you Chris S. (#4). I was one of those jerks. I grew up in a violent and unpredictable home. What I know now is that I suffered (terribly) from overwhelming anxiety and depression. I was rageful. And essentially, I brought my parents to school with me each day. So whose responsibility was it to help me understand my world so I could relax enough to learn? I don't know... BTW, we have a saying, "Once you meet the parents you can forgive the children".



Special education is for kids with some learning difficulties or lower IQs. Gifted programs are for kids who are very talented in specific categories. Jerkdom however is an equal opportunity designation. It's open to people of all ability levels. If you don't believe me, talk to teachers of gifted programs. If you want a real earful, ask them about the life-skills of some of those gifted students' parents. Poor parenting skills show up in all demographics.

Also, as an educator of Asperger's kids & their teachers & parents, let me assure you that your academic success has little correlation to your value to our society. It's what you do, not what you know that matters. But I have a feeling you'll figure that out sometime in the next few years.

As for all y'all rest of the commentators here, I don't have a clue how I'd solve the problems you face. I'm just glad you all have the passion to keep looking for solutions. As the parent of a kid who's distruptive behavior comes with his diagnosis (and whom I've pulled out of the classroom when necessary for his benefit as well as his classmates) I want to thank all of you for reaching out to our kids -- all of our kids. Kids who aren't disruptive deserve an education just like every other sub-group out there, not just the gifted or special needs or disadvantaged or fill-in-the-blank. How are you going to design a system to educate everyone? I don't have a clue. I just want to thank you all for keeping up the good fight.



How do the researchers account for unreported domestic violence and/or sexual abuse of children?


I taught elementary school one of the poorest neighborhoods in one of the poorest states in our great country. From what I saw, the jerks were few and far between (and mostly took the form of adult administrators and bullying teachers).

Occasionally there was a jerky child, but mostly what I saw were children with limited problem-solving skills (because they're children with little experience at navigating trouble) who were doing their best and acting out when they had reason to act out. I saw children who were growing up in single-parent homes or being raised by non-parental relatives or living in homeless shelters or in homes with one or more abusive or addicted parent. I saw children grappling with not having enough to eat and being fed junk in school cafeterias. I saw children dealing with overcrowded classrooms and outdated teaching materials. I saw children who did not speak English who were still attempting to navigate a system that denied them remedial English classes or even ESL classes so that they could transition into non-ESL/regular classes. I saw children trying to figure out how to reach teachers--and not, very often, teachers trying to reach children. I saw children set up to fail by a system that tsk-tsks and moves on when children what is expected of them--that is, fail.

All children are victims in and of such a system. I'd like to see adults navigate such a system as heroically as some children do.



"Frankly, as a student going into my junior year of high school, I'd probably find a way to get the teacher fired or suspended if they concentrated on the worst students instead of the best. Thank God for private schools that can concentrate on only having the best and brightest in their classrooms.

- Posted by Lucas"

Ah yes, another over-empowered, entitled student!
Lucas, when you get to the real world, you'll be working with some of those "worst students" and possibly even for some of them.

Best of luck to you!


@Holden Lewis

Casting out the undesirables worked in ancient Greek city states but it would not work today. The goal of our educational system (and the reform/prison system) is to maximize the productivity and sociability of citizens for the sake of a stronger state. Prisons are very ineffective at this and focus on confinement. Mixing obedient and troubled students in schools is an economic compromise that will stay until a more effective system is implemented or we cant afford it anymore. The mix also resembles a lot of companies and helps the "bright" operate effective in groups with the "troubled".

Finally, the US is rich enough to afford a democratic society where the weak are helped by the strong. If we fall off our golden horse, we may have to slide back to aristocracy that you wonder about, but that would not be the US anymore.

As for the study, I wonder how they chose to focus on domestic violence. Was this the strongest correlated of publicly available factors? What other factors did they consider? Or did they presume that domestic violence will cause kids to be troublemakers and just tested their hypothesis? This would build in a bias before the first bean is counted.

As many comments above say, domestic violence may very well be an ambivalent factor, causing some to be really studious and others disruptive - meaning that something else causes disruption.

I'm gonna test out the four jerks rule. I never took it as anything but slightly cynical shorthand, but the discussion of the intricacies of the cynicism hidden in it was rather enjoyable.

I do have to roll my eyes at the whole "I hope my sons are not ..." of the concerned parent. That's a bit too dramatic for this context. Dont you think?