Cutting, burning, or purposely injuring one’s body to cope with stress.

A small peer group composed of roughly six teenagers who have similar attitudes and who share activities.

In Lawrence Kohlberg’s theory, the intermediate level of moral reasoning, in which people respond to ethical issues by considering the need to uphold social norms.

A close-knit, delinquent peer group. Gangs form mainly under conditions of economic deprivation; they offer their members protection from harm and engage in a variety of criminal activities.

G. Stanley Hall’s phrase for the intense moodiness, emotional sensitivity, and risk-taking tendencies that characterize the life stage which he labeled adolescence.

David Elkind’s term for the tendency of young teenagers to believe that their lives are special and heroic; a component of adolescent egocentrism.

Any afterschool program or structured activity outside of the school day that is devoted to promoting flourishing in teenagers.

A research procedure designed to capture moment-to-moment experiences by having people carry pagers and take notes describing their activities and emotions whenever the signal sounds.

In Lawrence Kohlberg’s theory, the highest level of moral reasoning, in which people respond to ethical issues by applying their own moral guidelines apart from society’s rules.

Antisocial behavior that, for most teens, is specific to adolescence and does not persist into adult life.

David Elkind’s term for the tendency of young teenagers to feel that everyone is watching their every action; a component of adolescent egocentrism.

A relatively large teenage peer group.

Socialization of a young teenager into delinquency through conversations centered on performing antisocial acts.

In Lawrence Kohlberg’s theory, the lowest level of moral reasoning, in which people approach ethical issues by considering the personal punishments or rewards of taking a particular action.

The fact that despite living in poverty, going to substandard schools, and not having parents who speak the language, many immigrant children do far better than we might expect in school.

David Elkind’s term for the tendency of young teenagers to feel that their actions are at the center of everyone else’s consciousness.

Antisocial behavior that, for a fraction of adolescents, persists into adult life.

Jean Piaget’s fourth and final stage of cognitive development, reached at around age 12, and characterized by teenagers’ ability to reason at an abstract, scientific level.