It’s widely accepted in our society today that young kids’ behavior is a window into their future. When they can’t sit still in preschool, or they whack a friend, or they disobey─we recognize these as signs of portent. We all grasp that kids grow out of it, but it’s often hard to keep that in mind in the moment. Our vigilance has been piqued by the ADHD phenomenon, which is both good and bad. It’s good in the sense we want to spot hyperactivity early, in order to help kids who need it. It’s bad in the sense that we judge ordinary childhood misbehaving pretty harshly, through the lens of diagnoses.

Amidst these trade-offs, there’s common ground─a baseline that educators and parents agree on: children with better behavior at the start of kindergarten are more ready to learn. Behavior and attention go hand in hand. Better behavior leads to improved attention, which in turn leads to soaking up more knowledge. This behavioral-advantage, it’s understood, continues for several years. Surely, kindergarten behavior correlates well with third-grade achievement. This conventional wisdom was so accepted that few scholars felt they needed to double-check it.

However, it turns out not to be true. One simply must be very careful prematurely judging early childhood behavior. And this has really thrown a wrench into the field of child development, which hasn’t accepted this fact easily.

For Ashley and I, it started at a conference in Boston about two years ago. We were interested in how well kindergarten IQ tests predict elementary-school achievement (a subject we wrote about in our chapter "The Search for Intelligent Life in Kindergarten"). At the conference, we were discussing this with one of our favorite scholars, Columbia’s Dr. Jeanne Brooks-Gunn. She had recently published a massive analysis with UC Irvine’s Dr. Greg Duncan and 10 other coauthors. They combed through the data from six long-term population studies─four of which were from the United States, one from Canada, and one from the United Kingdom: 34,000 children in total were monitored for many years.

That night, I found Duncan and Brooks-Gunn’s paper. As expected, it confirmed that IQ tests at kindergarten only correlated with later achievement at r = 0.4. Since I’d seen this association before, in smaller studies, it didn’t surprise me. Instead, what jumped off the page was something else entirely. Measures of children’s behavior and social skills at kindergarten did not correlate with achievement, even just a few years later. Being better-behaved at the start of kindergarten barely mattered. The correlation was only r = 0.1. What this meant was that many kids who turned out to be very good students had been fidgety, disruptive, and prone to misbehavior at age 5. And many of the kids who were well-behaved at age 5 didn’t turn into such good students.

Ashley called Greg Duncan. He explained that their finding was completely contradictory to what they expected. The analysis had taken three years, and the pattern slowly emerged.

One scholar who simply didn’t believe the finding was the University of Virginia’s Dr. David Grissmer. He had devoted years to studying the achievement gap between black, Hispanic, and white students, using the Early Childhood Longitudinal Survey of entering kindergarten students (ECLS-K) and the Early Childhood Longitudinal Survey of a birth cohort (ECLS-B). Intimately familiar with this longitudinal data, Grissmer set out to disprove Duncan’s statistic.

At the Society for Research in Child Development conference last April in Denver, a special panel was convened to debate Duncan’s numbers. Everyone expected David Grissmer to explain how Duncan got it wrong. Instead, Grissmer explained that he’d run the numbers many times, and actually, Duncan got it right. The numbers didn’t lie. If anything, the true correlation was even lower than r = 0.1. Behavior is just not the reliable prognosticator we imagine it to be. (Duncan is now president of the Society for Research in Child Development.)

I’m telling this story to echo several other things on my mind. One reason is that in the last week on this blog, we’ve been debating Daniel Goleman about the value of teaching socio-emotional learning in schools. As we looked into these programs, we were struck by how harshly children’s behavior is judged─there’s a lot of pent-up anger, educators and parents wishing kids would stop acting their age and just be more mature. Bad behavior (of the ordinary sort) is perceived as undermining of scholastic progress. But the science doesn’t support this.

Another echo is to this wonderful column yesterday by Tony Dokoupil. To paraphrase, there’s a lot of science (not just the study cited by Dokoupil) which describes the trade-off of reasoning with young kids. You can demand obedience, or you can appeal to reason. Of course, young kids don’t reason very well, so in the short term, children of parents who reason tend to act out more─they’re simply not as obedient. But long term, encouraging kids to reason scaffolds complex thought, language development, and independent thinking. In the long term, children of parents who appeal to reason turn out better─especially at school.

In light of this research, our harsh judgment of children’s misbehavior is short-sighted. We’ve made a trade-off that’s ultimately good for kids. To turn around now and condemn this misbehavior is ignorant of how children typically develop.