• In Olweus's Norwegian National Survey data, as well as many other studies, the percentage of students who reported being bullied at school decreased with increasing age and grade level. In fact, such studies indicate that there are approximately twice as many victims of bullying in the primary grades as in the secondary grades. In contrast, the number of self-reported bullies remained fairly stable across the years.
  
  
• According to the NICHD survey, as well as many other studies, the typical trajectory of bullying is an increase and peak after elementary school, during the middle school years, followed by a decrease during the high school years. If this is the case, then the transition from elementary to middle school would be a particularly critical period for prevention and intervention efforts. When asked about this inconsistency in the bullying literature, Susan Swearer, assistant professor of school psychology at the University of Nebraska-Lincoln and principal investigator of a comprehensive program of research examining the ecology of bullying and victimization in school-aged youth, made the following comment:

"I think that perhaps the most accurate statement is that bullying takes on different forms across the lifespan. For example, bullying in elementary school may be more physical and therefore, more easily observed. Bullying in high school may be more akin to sexual harassment and thus, more covert and less observable. Most research suggests that bullying peaks during the middle school years and researchers have hypothesized that the transition from elementary to middle school, the need to re-establish peer relationships, and puberty may all account for this 'increase.' In any case, I think the most defensible statement is that bullying is a problem across all ages!"