Peer Violence Among Teenagers: Trends in Violence and Threats of Violence in Schools: 1991-2010

by Kenneth C. Land (Duke University) / August 1, 2012

A special Child Well-Being Index (CWI) report from Duke University tracks trends over time in percentages and numbers of middle and high school students exposed to four forms of peer-to-peer adolescent violence in schools, specifically: threat without injury; threat with a weapon without injury; intentional injury without a weapon; and injury with a weapon. These four activities represent the most extreme forms of bullying.

National data showing how cyberbullying or other kinds of teasing and tormenting among teenagers has changed over time are not now available. However, 15 years of research on CWI indicate that trends in violence tend to move together. The researchers, therefore, believe that the trends in adolescent violence found in Monitoring the Future (MTF), the annual, federally funded survey of teens which forms the basis of this report, can be used to understand general trends in bullying.


  • Until 2010, more teens in middle and high schools were threatened than actually injured; these trends have now merged so that both threats and injuries occur at the same level.
  • Trends in numbers of middle and high school students exposed to all four forms of violence began to increase in 2002 and 2003, peaked between 2007 and 2008, and began to decrease around 2008 and 2009.
  • The annual numbers of adolescents injured intentionally without a weapon showed the greatest fluctuation. Injury without a weapon increased dramatically from 2003-2007, flattened out in 2008-2009, and declined slightly in 2009-2010.
  • All four forms of violent bullying in schools show evidence of increases in the estimated numbers of middle and high school victims in the early 1990s – prior to the most recent peaks. It has been noted, however, that the 2002-2008 years were a period of increased access to the Internet and other forms of electronic communication and the creation and spread of social networking media.