The latest numbers show about eight percent of American kids drop out of high school before graduating. Want to keep your kids from becoming a statistic? Then pay attention to how they do in the sixth grade.

New research from Harvard University shows a strong correlation between students’ middle school experiences and whether they wind up doing well academically in high school.

It seems the transition from elementary to middle school — which typically happens in the sixth grade — is particularly critical. In fact, kids in the study who had to switch schools at that point experienced a “sharp drop” in math and language arts, while their peers who attended the same school from kindergarten to eighth grade did not.

The explanation? The study says “structural school transitions — or being in the youngest cohort in a school — adversely impact student performance.” In addition, city kids seemed to suffer the most. Since urban middle schools are often much larger than the elementary schools those children previously attended, it makes it that much easier to get lost in the shuffle.

Worse yet, lots of the best teachers avoid jobs in middle schools because “those students have a reputation for being difficult — hormones are flowing and violence is [often] a problem.”

Bottom line: pay special attention to your 10- and 11-year-olds. Students who fall behind in sixth grade have a tough time reversing the trend throughout middle and high school, making them more likely to eventually drop out of school entirely.

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