It's no secret that many young boys have trouble sitting still in class and that gets them into trouble. What may be less clear is that poor behavior can bias a teacher against a student, affecting academic achievement as well. Jessica Lahey describes her realization that she was handing out discipline unevenly in a great Atlantic article.
"It seems that behavior plays a significant role in teachers' grading practices, and consequently, boys receive lower grades from their teachers than testing would have predicted. The authors of this study conclude that teacher bias regarding behavior, rather than academic performance, penalizes boys as early as kindergarten. On average, boys receive lower behavioral assessment scores from teachers, and those scores affect teachers' overall perceptions of boys' intelligence and achievement."