Latchkey kid

A latchkey kid, or latchkey child, is a child who returns to an empty home after school or a child who is often left at home with no supervision because their parents are away at work. Child can be any age, alone or with siblings.
History of the term.
The term refers to the latchkey of a door to a house, or home. The key is often strung around the child's neck or left hidden under a mat (or some other object) at the rear door to the property. The term seems to first appear in a CBC radio program called "Discussion Club – Topic: How War Affects Canadian Children" in 1942, due to the phenomenon of children being left home alone during World War II, when the father would be enlisted into the armed forces and the mother would need to get a job. Given that the "Discussion Club" participants are all familiar with the term and allude to it being in colloquial usage, it likely predates 1942. In general, the term latchkey designates "those children between the ages of five and thirteen who care for themselves after the school day until their parents or guardians return home".
More specifically for their purposes, the San Marino (CA) Public Library has defined a Library Latchkey Child as "one who on a regular basis is required by their parents or guardian to remain at the public library for extended periods of time after school in lieu of day care. 'Regular basis' is defined as three or more days per week. 'Extended period' is defined as two or more hours per day" (American Library Association 12).
The term latchkey kid became commonplace in the 1970s and 1980s to describe members of Generation X who, according to a 2004 marketing study, "went through its all-important, formative years as one of the least parented, least nurtured generations in U.S. history." Latchkey kids were prevalent during this time, a result of increased divorce rates and increased maternal participation in the workforce at a time before childcare options outside the home were widely available. These latchkey children, referred to as "day orphans" in the 1984 documentary, "To Save Our Children to Save Our Schools", mainly came from middle or upper-class homes. The higher the educational attainment of the parents, the higher the odds the children of this time would be latchkey kids.
Effects on children.
The effects of being a latchkey child differ with age. Loneliness, boredom and fear are most common for those younger than ten years of age. In the early teens, there is a greater susceptibility to peer pressure, potentially resulting in such behavior as alcohol abuse, drug abuse, sexual promiscuity and smoking. The behaviors might stem from "unspent energy, peer pressure to misbehave, or hostility because of the lack of appropriate adult attention". However, some children experience other effects, such as an early development of self-reliance, adaptation to difficult situations, and a desire to contribute to a visible need in the household.
Socioeconomic status and length of time left alone can bring forth other negative effects. In one study, middle school students left home alone for more than three hours a day reported higher levels of behavioral problems, higher rates of depression, and lower levels of self-esteem than other students.
Children from lower income families are associated with greater externalizing issues (such as conduct disorders and hyperactivity) and academic problems. This association was weaker for children from middle income families as compared to their supervised peers. In 2000, a German PISA study found no significant differences in the scholastic performance between "latchkey kids" and kids in a "nuclear family".
Positive effects of being a latchkey child include independence and self-reliance at a young age. Deborah Belle, author of "The After-School Lives of Children: Alone and with Others While Parents Work" suggests that being left home alone may be a better alternative to staying with baby-sitters or older siblings.
Legal issues.
The legality of the latchkey children's "alone time" varies with country, state and local area. In the United States, state and local laws typically do not specify any particular age under 18 when a child can be legally left without supervision. However, some states do have specific age restrictions.
Parents can be held accountable by child welfare, child protective services organizations, or law enforcement if children come to harm while left without supervision if, in the opinion of the agency, the children's age or other considerations made such a choice inappropriate. Legal issues also continue to be important concerns for those who work in libraries. They worry about the potential liability should an unattended child be hurt, molested or abducted while at the facility. This issue becomes critical, particularly at closing time when "parents who are late picking up their children also create safety and possibly legal problems."