Holden contrasts Stradlater’s personal habits with Ackley’s: whereas Ackley is ugly and has poor dental hygiene, Stradlater is outwardly attractive but does not keep his razor or other toiletries clean.Physical growth (particularly in males), and cognitive development can extend into the early twenties.According to Holden, Ackley is a supremely irritating classmate who constantly barges into the room, exhibits disgusting personal habits and poor hygiene, and always acts as if he’s doing others a favor by spending time with them. He prevents Holden from reading by puttering around the room and pestering him with annoying questions.Ackley further aggravates Holden by cutting his fingernails on the floor, despite Holden’s repeated requests that he stop.Adolescence is usually accompanied by an increased independence allowed by the parents or legal guardians, including less supervision as compared to preadolescence.In studying adolescent development, adolescence can be defined biologically, as the physical transition marked by the onset of puberty and the termination of physical growth; cognitively, as changes in the ability to think abstractly and multi-dimensionally; or socially, as a period of preparation for adult roles.
Such milestones include driving a vehicle, having legal sexual relations, serving in the armed forces or on a jury, purchasing and drinking alcohol, voting, entering into contracts, finishing certain levels of education, and marriage.
This deficiency was heightened by the increasing incidence of teenage pregnancies, particularly in Western countries after the 1960s.
As part of each country's efforts to reduce such pregnancies, programs of sex education were introduced, initially over strong opposition from parent and religious groups.
Major pubertal and biological changes include changes to the sex organs, height, weight, and muscle mass, as well as major changes in brain structure and organization.
(Suspended from a Crook County High School classroom in Prineville, Oregon in 2008 after a parent complained that it was offensive.