Tweens

Preadolescence, also known as pre-teen or tween, is a stage of human development following early childhood and preceding adolescence. It commonly ends with the beginning of puberty, but may also be defined as ending with the start of the teenage years. For example, dictionary definitions generally designate it as 10–13 years. Preadolescence can bring its own challenges and anxieties.

Being prepubescent is not the same thing as being preadolescent. Instead, prepubescent (and sometimes child) is a term for boys and girls who have not developed secondary sex characteristics, while preadolescent is generally defined as those ranging from age 10 to 13 years. Preadolescence may also be defined as the period from 9 to 14 years.

The point at which a child becomes an adolescent is defined by the onset of puberty or the beginning of the teenage stage. Adolescence is also viewed as ending with the teenage stage. However, in some individuals (particularly females), puberty begins in the preadolescence years. Studies indicate that the onset of puberty has been one year earlier with each generation since the 1950s.

One can also distinguish middle childhood and preadolescence – middle childhood from approximately 5–8 years, as opposed to the time children are generally considered to reach preadolescence. There is no exact agreement as to when preadolescence starts and ends, and research by Gesell et al. suggests that "chronological time...is by no means identical with developmental time" – the duration of the "inner" stages of growth' – or with physiological time.

While known as preadolescent in psychology, the terms preteen, preteenager or tween are common in everyday use. A preteen or preteenager is a person 12 and under. Generally, the term is restricted to those close to reaching age 12, especially age 11.Tween is an American neologism and marketing term for preteen, which is a blend of between and teen. People within this age range are variously described as tweens, preadolescents, tweenies, preteens, pubescents, junior highers or tweenagers.

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