Over the decades, the lines separating young- middle-aged-, and older adults have blurred, as indicated by a broadening of the appropriate years for making life decisions.  Not only are many people marrying later, but some are marrying earlier than ever.  Overall, women giving birth later, but some are having children earlier in their lives. Older people are retiring later, but some are retiring at a younger age.  The spread or variability (standard deviation) of age-based decisions has increased substantially, giving adults greater freedom from the traditional constraints of age. With these relaxed age norms has come a host of related social problems. The relaxation of age norms for adult decision-making has inadvertently blurred the boundaries between adults and teenagers, between teenagers and children.  This generalization of the phenomenon throughout the life cycle is responsible for the adultification of childhood. 
Eight year old girls are, to an increasing extent, being treated as sexual objects; bullying peaks in the 6th grade; larger numbers of girls are having oral sex or sexual intercourse by the age of 15; the pregnancy rate for girls 13-15 is on the rise; we are in the process of dismantling the juvenile justice system in favor of adult forms of punishment; and more and more children are left without adult supervision in the afternoons, as though they were miniature adults who are capable of raising themselves. 
Jack Levin is the American Sociological Association’s 2009 Winner of the “Public Understanding of Sociology” Award.  This short book communicates the power and importance of sociological thinking to major, worldwide social trends.  Ideal for use in undergraduate courses such as introductory sociology, social problems, and social change as well as more advanced courses in population, or sociology of aging.