Children who bully are more likely to do poorly in school, use drugs and alcohol, vandalize property and engage in other antisocial behavior.  They are also at higher risk to end up in prison.  One study showed that two-thirds of boys identified as bullies in 6th through 9th grade had been convicted of a crime by the time they turned 24; 40 percent had multiple arrests by age 30, according to the National Youth Violence Prevention Resource Center.