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23.6: Childhood

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    Child Labor

    The kids in Figure \(\PageIndex{1}\) from 1911 are just children. All of them are between eight and 12 years old — years you no doubt spent in elementary and middle school. For the children in the picture, those years were spent as coal workers in a Pennsylvania mine. Their job was to separate impurities from coal by hand. For ten hours each day, six days a week, they would sit on wooden seats, perched over chutes and conveyor belts, picking impurities out of the coal. The use of children to do this work began in the mid-1860s, before mandatory child education and child labor laws had been passed in the United States. Although public disapproval of the employment of children as coal workers existed by the mid-1880s, the practice did not end in the United States until the 1920s.

    Child labour coal 1911
    Figure \(\PageIndex{1}\): Child labor

    Defining Childhood

    This example of child labor from the early 1900s shows how greatly attitudes toward children and childhood have changed over the past century in the United States. Children used to be thought of as small versions of adults who should work to help support the family or at least “earn their keep.” We now know that children differ from adults in many ways besides their size, and we generally think of childhood as an idyllic time dominated by play, fun, and learning. However, even now, the definition of childhood varies. To start, childhood can be defined legally or biologically.

    • Legally, childhood is defined as the period of minority, which lasts from birth until adulthood (majority). The age of maturity varies by place and purpose. For example, in the United States, at age 18, you are considered an adult for military service, but a minor for buying alcohol.
    • Biologically, childhood is defined as the stage of a human organism between birth and adolescence. The first year of life is called infancy and is covered in the concept Infancy. The remaining years until adolescence are loosely divided into early childhood (one to five years), middle childhood (six to ten years), and pre-adolescence (11-12 years).

    Early Childhood

    Early childhood follows infancy, which ends at the first birthday. The first part of early childhood is toddlerhood when a child begins speaking and taking steps independently. Toddlerhood ends around age three when the child becomes less dependent on caretakers for basic needs. Early childhood continues with the preschool stage, which ends at about age five.


    A toddler is a child between the ages of one and three years old. The toddler years are a time of great physical, cognitive, and psychosocial development. The deciduous dentition continues to erupt during these years, and growth in size is still fairly rapid, especially between the ages of one and two years, although it is considerably slower than it was during infancy. The children in Figure \(\PageIndex{2}\) show physical and motor development that is typical of toddlers at this age: walking with help.

    Physical Development in Toddlers

    By their first birthday, most toddlers can pull themselves up to a standing position and walk with help, if not alone. They can also sit down without assistance. They have the motor skills needed to bang two blocks together, turn through the pages of a book by flipping several pages at a time, and use a pincer grasp to pick up objects. They may be able to drink from a cup, but probably not without frequent spills. They may also be able to play with a ball by rolling or tossing it.

    By the age of two years, toddlers can typically walk sideways and backward. They can also run, although they are likely to fall down often like the kids in Figure \(\PageIndex{2}\). Two-year-old toddlers can walk up and down stairs on both feet, one step at a time, while holding on to a rail or someone’s hand. They have the fine motor skills needed to build a tower of blocks that is six blocks high. They have also mastered drinking from a cup and can control a spoon well enough to feed themselves. In addition, they may be toilet trained, at least during waking hours.

    By the age of three years, children have reached the end of the toddler stage. Their gross motor skills have progressed to the point that they are good at climbing, and they can now climb stairs one foot per step. They have the fine motor skills needed to handle small objects and to do simple puzzles. They can copy a circle and build a tower of blocks nine blocks high. They are also able to undress with assistance.

    toddlers walking
    Figure \(\PageIndex{2}\): These children are apparently relishing their newly developed ability for bipedal locomotion.
    Toddler running and falling
    Figure \(\PageIndex{3}\): This two-year-old toddler loves to run, even when they fall.

    Cognitive and Psychosocial Development in Toddlers

    One-year-old toddlers can use one- and two-syllable words (such as “ball” and “mama") and they can understand several other words. They can follow simple commands, especially if the commands are given with associated gestures. They can probably bring you a toy if you point at it and say, “Please bring me the toy.” They understand that objects continue to exist even when they are out of sight. They connect names with objects and use gestures or words to refer to objects or actions, such as pointing at a book, raising their arms to be picked up, or saying “cup.” In addition, they can mimic actions, such as covering the eyes while playing peekaboo. They experience separation anxiety and may cling to their parents. Children at this age do not play with other children, although they may play alongside them, like the toddlers pictured in Figure \(\PageIndex{4}\).

    Two-year-old toddlers can use as many as 50 words, and they generally understand at least a couple of hundred more words. They can obey simple verbal commands and help dress and undress. They understand physical relationships, such as flipping a switch to turn on a light. They can search for hidden objects, solve problems through trial and error, and mimic adult behaviors, for example, by feeding a doll. They also demonstrate self-recognition (in a mirror), attachment to parents, and anxiety when separated from parents. On the other hand, they may start showing signs of independence. They frequently use the word “no” and may throw temper tantrums. Although temper tantrums may be a way of expressing strong emotions toddlers do not yet have the ability to express verbally, they may also be a way of showing growing independence and testing boundaries

    Three-year-old toddlers are able to speak in short simple sentences and ask questions. They also easily learn new words, including people’s names. They attempt to sing along with songs. They can anticipate routines and are well on their way to being completely toilet trained. By this age, toddlers can show preferences for toys or foods and know how to play games with simple rules. This is also the age at which many children start to have imaginary companions.

    toddlers Playing with Xylophones
    Figure \(\PageIndex{4}\): These toddlers are playing side by side but are not actually playing with each other.

    Toddler Dentition

    By the age of one year, toddlers have up to eight deciduous teeth — generally the four upper and four lower incisors. Between about 12 months and 15 months of age, the lower lateral incisors usually emerge. The four first molars typically emerge between ten and 16 months and the four canines between 16 and 20 months. The remaining deciduous dentition — the four second molars — generally emerge between 20 and 30 months of age. There is considerable individual variation in the ages at which the deciduous teeth emerge, but the sequence at which they emerge is similar in most children.

    Growth of Toddlers

    Table \(\PageIndex{5}\) shows typical weight and height ranges for toddlers at ages one, two, and three years old. The values are for well-nourished, healthy children in the United States. Children who are smaller than these values may still be well nourished and healthy because stature is determined by genes, as well as the environment. Children of small parents tend to be small as well.

    Table \(\PageIndex{5}\): Weight and Height of Toddlers
    Age (years) Weight (kg) Weight (lbs) Height (cm) Height (in.)
    1 8.3 – 10.4 18.3 - 22.9 72.4 – 77.5 28.2 - 30.2
    2 10.6 – 13.1 23.3 - 28.8 84.3 – 89.9 32.9 - 35.1
    3 12.9 – 15.6 28.4 - 34.3 91.4 – 98.0 35.6 - 38.2

    Toddlers generally experience about a 52 percent increase in weight from age one to age three, which is a much slower gain in weight than the nearly 200 percent increase in weight from birth to age one year. In terms of height, there is about a 26 percent increase from age one to age three. Again, this is a much slower rate of growth than the nearly 100 percent increase in height during the first year after birth.


    The preschool stage of early childhood generally refers to the ages four to five years — however, in some disciplines, such as psychology, the preschool stage may be extended to age six or seven.

    Physical Development in Preschoolers

    By the age of four, children typically can go downstairs one foot per step, skip on one foot, and pedal and steer a wheeled toy such as a tricycle. They can climb ladders and playground equipment, and they can run around obstacles with ease. They are able to build a tower with ten or more blocks and thread small wooden beads on a string. They can also reproduce some shapes and letters, and they can hold a crayon or marker with a tripod grasp as in Figure \(\PageIndex{5}\).

    4 years old child drawing
    Figure \(\PageIndex{5}\): A four-year-old child can grip a crayon with a tripod grasp.

    By the age of five, children can skip on alternate feet and may learn to walk on a balance beam and turn somersaults. They can catch a ball thrown from a meter away, touch their toes without bending the knees, and balance on either foot with good control for about ten seconds. They can also build a three-dimensional structure with blocks by copying from a picture or model, cut on a line with scissors, and demonstrate good control with a pencil or marker. By this age, children begin to color within the lines and can reproduce many shapes and letters. Some children are already learning to ride a bicycle, usually with training wheels.

    Cognitive and Psychosocial Development in Preschoolers

    The fourth year is generally the age at which young children ask the most questions. Their speech is almost entirely intelligible by this age, and they are beginning to use the correct past tense of verbs. They can talk about objects, people, and events that are not present. They can also recite simple songs and rhymes and state their first and last name (and sometimes their phone number!). They are likely to be able to count to 20 and may be starting to read very simple books with just a few words on each page. They can dress and undress with assistance, and attend to their own toilet needs. They may insist on trying to do things independently but tend to become easily frustrated when problems arise. They typically enjoy role-playing and make-believe activities, and they can cooperate with others and participate in group activities. By this age, they are beginning to establish close relationships with playmates.

    Five-year-old children generally have a vocabulary of at least 1,500 words, produce sentences of at least five to seven words, and can define words by function (e.g., a bed is to sleep in). They can recognize the humor in simple jokes, make up jokes and riddles, and enjoy making other people laugh. They can identify and name several colors, sort objects on the basis of two qualities (such as color and shape), and place objects in order by size. They can count past 20 and often up to 100, and they may recognize the numerals one to ten. They know what calendars and clocks are for, and some may be starting to tell time. They can also recognize and identify coins and may be starting to count money. In addition, they are able to dress and undress alone. Children of this age often have just one or two “best” friends, and they may show affection and care toward others, such as another child who is hurt.

    Growth of Preschoolers

    By the time children pass their fourth birthday, their rate of growth has slowed considerably. During the preschool years, children typically gain about 1.8 to 2.7 kg (4 to 6 lb.) per year and grow about 5.1 to 7.6 cm (2 to 3 in.) per year. By the age of five, the majority of children weigh between 16.5 and 20.3 kg (36.3 and 44.7 lb.) and stand about 105 to 114 cm (41.3 to 44.2 in.) tall.

    Middle Childhood

    Middle childhood is the life stage between early childhood and pre-adolescence. It covers the ages of six to ten years when most children are in elementary school. Children within this age bracket are more independent and physically active than they were in the preschool years, but few have experienced any of the physical changes of puberty. Children in this range are more involved with friends and are learning to think in more complex ways than during their preschool years. Although progress in most major areas of development is relatively gradual during middle childhood, the cumulative differences between children aged six and those aged ten are substantial (Figure \(\PageIndex{6}\)).

    6-year-old child
    Figure \(\PageIndex{6}\): (left) Six-year-old child and (right) Ten-year-old child.

    Physical Development in Middle Childhood

    Physically, the first several years of middle childhood are a time of steady development in abilities, such as agility, balance, and endurance. Muscle strength and coordination also improve from ages six to ten years, and movements become more controlled and graceful. During this period, children typically learn to ride a bicycle without training wheels (see Figure \(\PageIndex{7}\)). They also typically learn to jump rope, hit a baseball, and kick a soccer ball. They may learn more complex skills, as well, such as playing basketball, dancing, or playing a musical instrument.

    child on bike
    Figure \(\PageIndex{7}\): This child has just started riding a bike without training wheels.

    Cognitive and Psychosocial Development in Middle Childhood

    The period from six to ten years is a time of important cognitive changes. Generally, children in this age range develop more mature and logical ways of thinking. They gradually develop the ability to consider multiple parts of problems, although their thinking is still concrete, rather than abstract. Children in this age range also develop the ability to concentrate for increasing lengths of time. Whereas a six-year-old might be able to focus on a task for just 15 minutes and follow a series of only three commands, a ten-year-old might be able to focus on a task for more than an hour and follow a series of at least five commands. Language skills also improve during these years. A six-year-old typically uses complete but simple sentences with an average of only about six words. A ten-year-old uses much longer and more complex sentences with virtually the same grammar and pronunciation as adults.

    Emotionally, children aged six to ten years may be somewhat fragile. Their self-esteem may change rapidly depending on how they think others perceive them, especially their peers, as peer acceptance becomes increasingly important during these years. If children aren’t chosen for a team or are snubbed by a friend, for example, their self-esteem may plummet. Children in this age range also develop body modesty and express an increasing desire for privacy. Although school-age children sometimes seem like small adults as they buckle down to schoolwork and take on new responsibilities at home, they can also revert to more immature emotions and behaviors. They may sometimes seem as stubborn and unreasonable as toddlers during the “terrible twos,” and the occasional tantrum may still occur.

    From the ages of six to ten, children go from playing with same-gender friends to starting to play in mixed-gender groups. They may still like playing alone, but friends become increasingly important. They may enjoy playing on a sports team, like the Little League Baseball player in the picture below, or they may participate in scouts or other formal peer groups. They are generally good at cooperating and sharing, although they sometimes exhibit jealousy toward their peers or siblings.

    children playing soccer
    Figure \(\PageIndex{8}\): In middle childhood, many children enjoy participating in sports or other peer-group activities.


    The age range from about 11 to 12 years is called pre-adolescence or the “tweens,” and children in this age range are commonly called preteens. Pre-adolescence is considered a unique stage of development because it coincides with the start of puberty, although few of the obvious physical changes of puberty, such as sexual maturation, have yet to occur.

    Pre-adolescence is also a time of significant cognitive and psychosocial development. This is typically when young people finally develop the ability to think abstractly. They can think beyond their personal experiences, and they can view the world less in terms of absolutes, such as right or wrong, black or white. Pre-adolescents also develop the ability to identify the cause and effect sequences, although they still may not be able to infer motives or to reason hypothetically. Relative to earlier ages in middle childhood, preteens tend to:

    • Have a more realistic and less fantasy-based view of life: They may worry about a scary media event (such as kidnapping), but they no longer fear the monster under the bed. They may want to be an engineer — rather than a wizard— when they grow up.
    • Think and act more reasonably and less emotionally: They might earn money to buy what they want, rather than throw a tantrum when it isn’t given to them on demand.
    • Start developing a sense of identity: They may have increased feelings of independence and individuality, and no longer feel like just “one of the family.”
    • Care more about their appearance and what they wear.
    • Start to have romantic feelings toward a peer, and may experience “puppy love.”

    Dentition in Middle Childhood and Pre-Adolescence

    Middle childhood is the time when the deciduous teeth loosen and fall out, and most of the permanent teeth emerge. The first deciduous teeth to fall out are generally the eight incisors, which are typically lost between the ages of six and eight (Figure \(\PageIndex{9}\)). The incisors are followed by the eight premolars, which are generally lost between the ages of nine and 12, and by the four canines, which are generally lost between the ages of ten and 13. The second permanent molars generally emerge between the ages of 11 and 13. The only permanent teeth that emerge later are the third molars (or wisdom teeth) which generally emerge in late adolescence or early adulthood.

    Smile with missing tooth
    Figure \(\PageIndex{9}\): This happy-go-lucky six-year-old just lost their first baby tooth, their left lower central incisor.

    Growth in Middle Childhood and Pre-Adolescence

    For most children, physical growth is slow and steady during middle childhood, although there may be a few brief growth spurts separated by periods of slower growth. In middle childhood, children generally gain an average of about 3.2 kg (7 lb.) per year and increase in height by an average of about 5.8 cm (2.3 in.) per year. By the age of 12, the average child weighs about 41 kg (91 lb.) and has a height of about 150 cm (59 in.). There is very little difference in size between different sexes at this age. Some of the weight gain during middle childhood generally reflects an increase in muscle mass relative to the muscle mass of the preschool child. Some children may begin the adolescent growth spurt during pre-adolescence, but most of this period of rapid growth occurs during adolescence.

    Feature: Reliable Sources

    In most of the United States, today’s kindergarten is yesterday’s first grade in terms of the academic skills that children are expected to master. This suggests that pre-K (pre-school) programs are the new kindergarten. Many studies have demonstrated that children who attend quality pre-K programs not only do better throughout the remainder of their school years but also tend to be more successful as adults. Such studies provided the impetus in many states to fund public pre-K education for all students who cannot afford private pre-K programs.

    A study reported in 2016 has caused many people to reconsider the value of pre-K education. Undertaken in Tennessee by researchers at Vanderbilt University, the study found that the state’s newly funded voluntary program for low-income preschoolers had only fleeting benefits. Children who attended the program did better in the first year of school than control-group children who did not attend a pre-K program. However, by third grade, children in the control group had actually surpassed the children who had attended the state’s pre-K program.

    Not surprisingly, the Tennessee study was very controversial, and it has raised a number of questions. Have the long-touted benefits of pre-K education been over-rated? Does pre-K education really have no lasting impact on children and their success in school and life? Is investing in public pre-K programs a waste of limited educational dollars? Or is the real issue high-quality pre-K versus low-quality pre-K? The Tennessee pre-K program that was the focus of the Vanderbilt study has been criticized for being poorly executed and under-funded. Would a higher-quality pre-K program have produced the positive results found in several other studies? And why did the children who attended the program initially do better than the control group, but then later perform worse? Was something about the education they were receiving at the kindergarten through third-grade level "undoing" the benefits of pre-K?

    Research the issue of pre-K education and its pros and cons. Try to find the most up-to-date, evidence-based studies and discussions of the issue. After finding several reliable resources, form your own conclusions about the value of pre-K education. Keep in mind that a reasonable conclusion need not be definitive. In other words, it may be appropriate to conclude that there is not yet enough reliable evidence to assess whether or not pre-K programs are a good investment. Your conclusion should also be open to revision as new evidence becomes available.


    1. Contrast legal and biological definitions of childhood.
    2. List the stages of biological childhood.
    3. Define early childhood. What are its two main divisions?
    4. Give examples of the range of developments that occur during early childhood.
    5. How does the rate of physical growth during early childhood compare to the growth rate during infancy?
    6. What changes in dentition occur during early childhood?
    7. Define middle childhood and identify the range of years it covers.
    8. Describe some of the changes that take place during middle childhood.
    9. What is pre-adolescence, and when does it occur?
    10. What are some of the main developmental events that happen in pre-adolescence?
    11. Summarize changes in dentition and body size that occur during middle childhood and pre-adolescence.
    12. If a toddler weighs 20 pounds at one year of age, which of the choices below is most likely her weight at age three, assuming typical growth?
      1. 22 pounds
      2. 25 pounds
      3. 30 pounds
      4. 40 pounds
    13. Describe how the interaction between peers changes from the beginning to the end of biological childhood.
    14. True or False: By the age of ten, boys are significantly larger than girls, on average.
    15. True or False: Tantrums only occur during the early childhood years.


    1. Child labor coal by Lewis Hine, public domain via Wikimedia Commons
    2. Friends by Cheryl Holt, via Pixabay license
    3. Toddler running and falling by Jamie Campbell, licensed CC BY 2.0 via Wikimedia Commons
    4. Playing with Xylophones by Donnie Ray Jones, licensed CC BY 2.0 via Flickr
    5. Child drawing by D. Sharon Pruitt, licensed CC BY 2.0 via Wikimedia Commons
    6. Operation good heart by US Army, public domain via Wikimedia Commons
    7. Boy on bicyle by cegoh via Pixabay license
    8. Children playing released CC0 via Pxhere
    9. Smile with missing tooth by crimfants, licensed CC BY 2.0 via Wikimedia Commons
    10. Text adapted from Human Biology by CK-12 licensed CC BY-NC 3.0

    This page titled 23.6: Childhood is shared under a CK-12 license and was authored, remixed, and/or curated by Suzanne Wakim & Mandeep Grewal via source content that was edited to the style and standards of the LibreTexts platform.

    CK-12 Foundation
    CK-12 Foundation is licensed under CK-12 Curriculum Materials License