These findings are alarming, especially in light of the fact that challenging behaviors are one of the strongest predictors of more serious problems as kids grow older, including delinquency, aggression, anti-social behavior, and substance abuse. What’s going on? More importantly, what can we do about it? Many researchers view the continuing rise in bad preschooler behavior as an indication of the need for change in school programs and classroom management. But it’s also up to parents to set limits for their children, and to avoid pushing them too hard, too soon.