Nationally, one in six children miss 15 or more days of school in a year and are considered chronically absent. As you know, school leaders have long lamented the missed instruction that has now reached crisis levels.

The fear is that these chronically absent students suffer academically because of all the classroom instruction they miss. In 2015, the U.S, Secretary of Education and other federal officials responded to this perceived crisis, urging communities to “support every student, every day to attend and be successful in school[.]”

And worrying about whether children attend school makes sense. After all, if students don’t show up, teachers can’t teach them, as reminded by an article in The Conversation.

But what if America’s attendance crisis is about much more than students missing class? What if, instead, it is a reflection of family and community crises these students face — such as being evicted from the family apartment, or fearing for their safety in their neighborhood or suffering from an illness? These circumstances can both limit children’s academic achievement and keep them from getting to school.

A group of social scientists recently studied inequality in schools, investigating how excused and unexcused absences relate to children’s academic achievement. The study tracked how both types of absences are linked to elementary school reading and math test scores in Madison, Wisconsin, home to a diverse urban school district.

The study found that absences excused by a parent or guardian do little to harm children’s learning over the school year. In fact, children with no unexcused absences — but with 15 to 18 excused absences — have test scores on par with their peers who have no absences.

Meanwhile, the average child with even just one unexcused absence does much worse academically than their peers who have none. For example, in the study, the average student with no unexcused absences was at the 58th percentile of math test scores. The average student with one unexcused absence was at the 38th percentile. But the average student with 18 unexcused absences was at the 17th percentile.

Does this mean schools shouldn’t worry about a student’s education as long as a parent calls in each time the child misses class?

Not exactly.

But the findings don’t make sense if absence from school affects achievement mainly because kids miss class time.

That is most apparent when considering the relationship between 18 unexcused absences and test score achievement. Accounting for differences among students unrelated to the current year of instruction — including their health conditions, prior academic achievement, and family education and income — explains 88% of that relationship. That means children with so many unexcused absences would almost certainly have similarly low test scores even if their parents called in or if they had attended school more regularly.

Instead, the scientists believe an unexcused absence is a strong signal of the many challenges children and families face outside of school, including economic and medical hardships, as well as insecurity around food, housing, transportation and family.

In other words, unexcused absences can be a powerful signal of how those out-of-school challenges affect children’s academic progress.

To be clear, evidence from the study suggests unexcused absences are problematic, but for a different reason than people often think. Absence from school, and especially unexcused absence, matters mainly as a signal of many crises children and their families may be facing. It matters less as a cause of lower student achievement due to missed instruction.

How researchers and the public choose to think of school absences matters for educational policy. National, state and school district attendance policies typically hold schools and families accountable for all of the days children miss, regardless of whether they were excused or unexcused absences.

These policies assume that missing school for any reason harms children academically because they are missing classroom instruction. They also assume that schools will be able to effectively intervene to increase academic achievement by reducing student absences.

As a result, these attendance policies end up disproportionately punishing families dealing with out-of-school crises in their lives and pressuring those who serve them to get students to school more often.

A new solution: using unexcused absences from school as a signal to channel resources to the children and families who need them most.