I spent a day at my oldest daughter’s elementary school this past year, and wow. I never thought I could learn so much from going to elementary school in my mid-30s.

In six hours I got a whole schoolbusful of education—about human nature.

This school operates a program that invites students’ fathers to be on campus throughout the day, serving as an extra pair of eyes scoping the halls for potential threats, and an extra set of hands helping in the classrooms. Great program—especially considering the fact that at this school, every last one of the teachers and administrators is a woman. The only male role models these kids see during school hours are these fathers.

I witnessed some pretty impressive things in some classrooms. One teacher in particular had her fourth graders breaking down sentences grammatically with jaw-dropping precision. As a group, they were reciting rules about semantic gradability and inflectional morphology—whatever those are. I’m calculating how inexpensive it would be to hire myself a 9-year-old grammar tutor.

In other classrooms, however, far less learning was going on. As teachers instructed, private conversations bubbled. Virtually any distraction derailed students from the task at hand. Students spoke out, apparently, whenever thoughts popped into their heads—even rude ones.

I’m no expert in elementary education, but I believe I can distill the difference between the fruitful and the unfruitful classrooms down to a single factor: the teacher’s determination to confront bad behavior.

Put a bunch of kids together, and you’re bound to see some of that. It may start small. But if it isn’t confronted—and if necessary, removed—it spreads. Just like the stomach virus that seems to wallop the entire elementary school every couple of months because parents ignore quarantine. It’s true what the Bible says about a little leaven.

A child talks while the teacher is instructing. If nothing happens, human nature whispers in the next kid’s ear: Huh! I guess it’s OK to do that. So he talks too. Some other kid thinks, Well, if he can do that—then I’ll do this. In no time, the room sounds like Grand Central Station.

Isn’t that amazing? Sometimes I think children are hardwired to continue getting louder until someone tells them enough.

The truth is, they are getting louder specifically to test how long it takes before someone tells them enough.

The teacher with the intestinal fortitude to truly confront the problem can quickly transform the unruliness into “ruliness.”

“When it comes to rearing children, every society is only 20 years away from barbarism,” Dr. Albert Siegel once wrote. “Twenty years is all we have to accomplish the task of civilizing the infants who are born into our midst each year. These savages know nothing of our language, our culture, our religion, our values, our customs of interpersonal relations. … The barbarian must be tamed if civilization is to survive.”

It’s a bit dramatic—but in a sense painfully true. Calling children savages certainly reflects reality far better than treating them like natural-born saints, sages and savants. Our Satan-inspired human nature represents a savage within each of us that must be civilized. Children have it in spades—unless we are diligent in confronting it. That’s why Proverbs 29:15 says, “The rod and reproof give wisdom: but a child left to himself bringeth his mother to shame.”

Where this reality truly smacked me in the face was on the playground at my daughter’s school. I spent three recesses outside—with first graders, then second graders, then fifth graders. Each successive mob was worse behaved. The fifth graders, having lived more years without being properly civilized, were genuine specimens of savagery. Everywhere I turned, I saw carnality on parade: name-calling, accusing, cursing, screaming, boasting, pushing, sulking, cheating.

I realized that most of these same kids had just been inside under the authority of effective, qualified teachers who had managed to keep a lid on this ugliness through productive, focused work. The level of human nature suddenly on display correlated precisely with the lack of government in their lives at that moment.

Take a good student out of the structure of a disciplined classroom and turn him loose with 60 other kids and virtually no supervision, and you have The Lord of the Flies.

I hate to admit it, but the same is true of the barbarians living in my own house. There are three of them, not counting my wife and me (who, despite the indwelling civilizing agent of the Holy Spirit, still have our moments).

Here is what I have noticed. Every time my family gets overly busy and I in particular begin letting events overtake us, then the savages begin their parade. If my wife and I aren’t really paying attention, it gets louder and uglier until it’s too obvious to ignore and we step in with a firm enough.

That’s not the way God intended family to be. Yet it may not be exaggerating to say that this “ignore the barbarians until they drive you mad” form of child training is the number one method employed in the Western world today. I’m still trying to figure out how elementary school educators believe that allowing children a half hour of barbarism on the playground to break up the day helps round them out.

There is much to be said for maintaining a steady presence of civilizing forces in our children’s lives: activities, instruction, discipline, reading, games, work, chores, crafts, charts, schedules, rewards, punishments, supervision. Kids crave structure. When it isn’t there, they act out until they get it. When they get it, it frees them up to achieve some amazing things.

Don’t get me wrong. Family isn’t boot camp. It doesn’t necessarily take enormous effort to steer clear of pandemonium in favor of structured or even lightly supervised play. And it’s not that children shouldn’t be given enough room to make mistakes. Beware getting into a negative cycle of criticizing them for every word or deed that proves that they are what they are: unconverted little people who aren’t yet civilized.

We need to make sure the overall message we’re sending is a positive one: When we do things decently and in order—as God does—life is happier, more fun, more rewarding in every way.

As our children grow, the responsibility for structuring their lives and bridling themselves must gradually shift onto their own shoulders. They need practice at civilizing the savage within. Otherwise, the moment they’re on their own, they’ll turn into big versions of the fifth graders on that playground. If you want to know what that looks like, visit an American university.

The task of civilizing the infants born into our midst is crucial—and great. Twenty years is all we have.