The treatment in the "Language" sections in this article deals specifically with a child's acquisition of the English language and does not represent a worldwide view of the subject. Please improve this article and discuss the issue on the talk page. (August 2010)
Child development stages are the theoretical milestones of child development, some of which are asserted in nativist theories. This article discusses the most widely accepted developmental stages in children. There exists a wide variation in terms of what is considered "normal", caused by variations in genetic, cognitive, physical, family, cultural, nutritional, educational, and environmental factors. Many children reach some or most of these milestones at different times from the norm.[1]
Holistic development sees the child in the round, as a whole person – physically, emotionally, intellectually, socially, morally, culturally and spiritually. Learning about child development involves studying patterns of growth and development, from which guidelines for 'normal' development are construed. Developmental norms are sometimes called milestones – they define the recognized development pattern that children are expected to follow. Each child develops in a unique way; however, using norms helps in understanding these general patterns of development while recognizing the wide variation between individuals.
Approximate outline of development periods in postnatal human development until what generally is regarded as adulthood. There are no universally unanimous definitions, so they vary considerably, but generally fall within the faded intervals at the flanks of the periods.
Can execute simple gymnastic movements, such as somersaults.
Uses a vocabulary of several thousand words.
Demonstrates a longer attention span.
Uses serious, logical attention span.
Able to understand reasoning and make the right decisions.
Contingent upon the health of the child.
Desires to be perfect and is quite self-critical,
Worries more, may have low self-confidence.
Tends to complain, has strong emotional reactions.
8 years
The child can tie his or her shoelaces.
The child can draw a diamond shape.
The child become increasingly skilled in hobbies, sports, and active play.
Have well-developed speech and use correct grammar most of the time.
Become interested in reading books.
Are still working on spelling and grammar in his or her written work.
Contingent upon the health of the child.
Show more independence from parents and family.
Start to think about the future.
Understand more about his or her place in the world. pay more attention to friendships and teamwork.
Infancy
Newborn
Physical development
Infants are usually born weighing between 5 pounds 8 ounces (2,500 g) and 8 pounds 13 ounces (4,000 g), but infants born prematurely often weigh less.[17]
Newborns typically lose 7–10% of their birth weight in the first few days, but they usually regain it within two weeks.[17]
During the first month, infants grow about 1 to 1.5 inches (2.5 to 3.8 cm) and gain weight at a rate of about 1 ounce (28 g) per day.[17]
Resting heart rate is generally between 70 and 190 beats per minute.[18]
The rooting reflex, which causes the infant to suck when the nipple of a breast or bottle is placed in their mouth.[19]
The Moro reflex, which causes the infant to throw out their arms and legs when startled.[19]
The asymmetrical tonic neck reflex, which is triggered when the head is turned to one side and causes the infant's arm on that side to straighten and the arm on the other side to bend.[19]
The palmar grasp reflex, which causes the infant to grasp a finger placed in their palm and to curl their toes when the soles of their feet are touched.[19]
Enjoys soft and coarse sensations and does not like rough handling.[22]
Two months old
Physical development
Typically grows at a similar rate to the previous month, usually growing between 1 and 1.5 inches (2.5 and 3.8 cm) and gaining about 2 pounds (910 g).[23]
Resting heart rate is usually between 80 and 160 beats per minute, and it typically stays within that range until the infant is about one year old.[18]
Motor development
Can hold up head and chest while in prone position.[24]
Communicates and expresses more using face and body.[27]
Four months old
Physical development
By this age, infants may have doubled their birth weights. They typically grow about 0.8 inches (2.0 cm) and gain about 1 to 1.5 pounds (450 to 680 g) during this month.[28] Fat rolls ("Baby Fat") begin to appear on thighs, upper arms and neck.
Able to stand with help and bounce while standing.[31] An explorative study found, however, that 3- to 5-month-old infants can be taught independent standing, which was considered safe.[32]
More teeth appear, often in the order of two lower incisors then two upper incisors followed by four more incisors and two lower molars but some babies may still be waiting for their first.
Arm and hands are more developed than feet and legs (cephalocaudal development); hands appear large in proportion to other body parts.
Legs may continue to appear bowed.
"Baby fat" continues to appear on thighs, upper arms and neck.
Feet appear flat as arch has not yet fully developed.
Both eyes work in unison (true binocular coordination).
Can see distant objects (4 to 6 m or 13 to 20 ft away) and points at them.
Motor development
Reaches with one hand leading to grasp an offered object or toy.
Adjustment from grip emerges around 8 months.
Manipulates objects, transferring them from one hand to the other.
Explores new objects by poking with one finger.
They adjust their grip based on touch at 8 months, not yet visual cues.
Infants will begin to use visual cues while reaching and grasping after 9 months of age.
Uses deliberate pincer grasp to pick up small objects, toys, and finger foods.
Stacks objects; also places objects inside one another.
Releases objects or toys by dropping or throwing; cannot intentionally put an object down because infants, at eight months, are not using visual sensory information while grasping an object.
Beginning to pull self to a standing position.
Beginning to stand alone, leaning on furniture for support; moves around obstacles by side-stepping.
Has good balance when sitting; can shift positions without falling.
Creeps on hands and knees; crawls up and down stairs.
The hip and knee joints exhibit a greater lag than the shoulder and elbow joints, which shows that motor skills develop in a cephalocaudal trend.
The lags between joints decreases as age increases.
The hip and knee joints are more strongly coupled than the shoulder and elbow joints in interlimb comparisons. This may be due to the weight bearing the hip and knee joints go through for standing and walking.
Walks with adult support, holding onto adult's hand; may begin to walk alone.
Walking alone leads to inconsistent steps, grasping objects for balance, and taking few steps without falling.
Walking usually occurs to explore environment and not necessarily to obtain a specific task, goal, or object.
Watches people, objects, and activities in the immediate environment.
Responds to hearing tests (voice localization); however, loses interest quickly and, therefore, may be difficult to test formally.
Recognizes objects in reverse
Drops thing intentionally and repeats and watches object
Imitates activities like playing a drum
Begins to develop expressive rather than receptive language – child actually responding to what is said to them instead of only receiving and watching the interaction.[36]
Early childhood
Toddler (12–24 months)
Physical
Weight is now approximately three times the child's birth weight.
Respiration rate varies with emotional state and activity.
Rate of growth slows.
Head size increases slowly; grows approximately 1.3 cm (0.51 in) every six months; anterior fontanelle is nearly closed at eighteen months as bones of the skull thicken.
Anterior fontanelle closing or fully closed, usually at the middle of this year.
Chest circumference is larger than head circumference.
Legs may still appear bowed.
Toddler will begin to lose the "baby fat" once he/she begins walking.
Body shape changes; takes on more adult-like appearance; still appears top-heavy; abdomen protrudes, back is swayed.
Stands alone with feet spread apart, legs stiffened, and arms extended for support.
Gets to feet unaided.
Most children walk unassisted near the end of this period; falls often; not always able to maneuver around obstacles, such as furniture or toys.
Children first recognize when to apply muscular force when walking in order to conserve energy; soon after, children learn to fine-tune muscle tissues to stabilize themselves.
Uses furniture to lower self to floor; collapses backwards into a sitting position or falls forward on hands and then sits.
Enjoys pushing or pulling toys while walking.
Repeatedly picks up objects and throws them; direction becomes more deliberate.
Attempts to run; has difficulty stopping and usually just drops to the floor.
Crawls up stairs on all fours; goes down stairs in same position.
Sits in a small chair.
Carries toys from place to place.
Enjoys crayons and markers for scribbling; uses whole-arm movement.
Helps feed self; enjoys holding spoon (often upside down) and drinking from a glass or cup; not always accurate in getting utensils into mouth; frequent spills should be expected.
Helps turn pages in book.
Stacks two to six objects per day.
Cognitive development
Enjoys object-hiding activities.
Early in this period, the child always searches in the same location for a hidden object (if the child has watched the hiding of an object). Later, the child will search in several locations.
Passes toy to other hand when offered a second object (referred to as "crossing the midline" – an important neurological development).
Manages three to four objects by setting an object aside (on lap or floor) when presented with a new toy.
Demonstrates understanding of functional relationships (objects that belong together): Puts spoon in bowl and then uses spoon as if eating; places teacup on saucer and sips from cup; tries to make doll stand up.
Shows or offers toy to another person to look at.
Names many everyday objects.
Shows increasing understanding of spatial and form discrimination: puts all pegs in a pegboard; places three geometric shapes in large formboard or puzzle.
Places several small items (blocks, clothespins, cereal pieces) in a container or bottle and then dumps them out.
Tries to make mechanical objects work after watching someone else do so.
Most children with autism are diagnosed at this age.
Language
Produces considerable "jargon": puts words and sounds together into speech-like (inflected) patterns.
Holophrastic speech: uses one word to convey an entire thought; meaning depends on the inflection ("me" may be used to request more cookies or a desire to feed self). Later, produces two-word phrases to express a complete thought (telegraphic speech): "More cookie", "Daddy bye-bye."
Follows simple directions, "Give Daddy the cup."
When asked, will point to familiar persons, animals, and toys.
Identifies three body parts if someone names them: "Show me your nose (toe, ear)."
Indicates a few desired objects and activities by name: "Bye-bye", "cookie"; verbal request is often accompanied by an insistent gesture.
Responds to simple questions with "yes" or "no" and appropriate head movement.
Speech is 25 to 50 percent intelligible during this period.
Locates familiar objects on request (if child knows location of objects).
Acquires and uses five to fifty words; typically these are words that refer to animals, food, and toys.
Uses gestures, such as pointing or pulling, to direct adult attention.
Enjoys rhymes and songs; tries to join in.
Seems aware of reciprocal (back and forth) aspects of conversational exchanges; some turn-taking in other kinds of vocal exchanges, such as making and imitating sounds.
Enjoys adult attention; likes to know that an adult is near; gives hugs and kisses.
Recognizes self in mirror.
Enjoys the companionship of other children, but does not play cooperatively.
Begins to assert independence; often refuses to cooperate with daily routines that once were enjoyable; resists getting dressed, putting on shoes, eating, taking a bath; wants to try doing things without help.
May have a tantrum when things go wrong or if overly tired or frustrated.
Exceedingly curious about people and surroundings; needs to be watched carefully to prevent them from getting into unsafe situations.
Young toddlers (12 months) have a wider midfoot than older toddlers (24 months).
The foot will develop greater contact area during walking.
Maximum force of the foot will increase.
Peak pressure of the foot increases.
Force-time integral increases in all except the midfoot.
The lateral toes did not show a pattern in development of walking.
Loading parameters of the foot generally increase, the midfoot develops opposite of the other regions in the foot.
Two-year-old
Physical
Posture is more erect; abdomen still large and protruding, back swayed, because abdominal muscles are not yet fully developed.
Respirations are slow and regular
Body temperature continues to fluctuate with activity, emotional state, and environment.
Brain reaches about 80 percent of its adult size.
16 baby teeth almost finished growing out
Motor development
Can walk around obstacles and walk more erectly.
Squats for long periods while playing.
Climbs stairs unassisted (but not with alternating feet).
Balances on one foot (for a few moments), jumps up and down, but may fall.
Often achieves toilet training during this year (depending on child's physical and neurological development) although accidents should still be expected; the child will indicate readiness for toilet training.
Throws large ball underhand without losing balance. Holds small cup or tumbler in one hand. Unbuttons large buttons; unzips large zippers.
Opens doors by turning doorknobs.
Grasps large crayon with fist; scribbles.
Climbs up on chair, turns, and sits down.
Stacks four to six objects on top of one another.
Uses feet to propel wheeled riding toys.
Most likely in the emerging stage of learning to run.
Cognitive
Eye–hand movements better coordinated; can put objects together, take them apart; fit large pegs into pegboard.
Begins to use objects for purposes other than intended (may push a block around as a boat).
Does simple classification tasks based on single dimension (separates toy dinosaurs from toy cars).
Seems fascinated by, or engrossed in, figuring out situations: where the tennis ball rolled, where the dog went, what caused a particular noise.
Attends to self-selected activities for longer periods of time. Discovering cause and effect: squeezing the cat makes them scratch.
Shows signs of empathy and caring: comforts another child if hurt or frightened; appears to sometimes be overly affectionate in offering hugs and kisses to children
Continues to use physical aggression if frustrated or angry (for some children, this is more exaggerated than for others); Physical aggression usually lessens as verbal skills improve.
Temper tantrums likely to peak during this year; extremely difficult to reason with during a tantrum.
Impatient; finds it difficult to wait or take turns.
Enjoys "helping" with household chores; imitates everyday activities: may try to toilet train a stuffed animal, feed a doll.
"Bossy" with parents and caregivers; orders them around, makes demands, expects immediate compliance from adults.
Watches and imitates the play of other children, but seldom interacts directly; plays near others, often choosing similar toys and activities (parallel play);[39] solitary play is often simple and repetitive.[40]
Offers toys to other children, but is usually possessive of playthings; still tends to hoard toys.
Making choices is difficult; wants it both ways.
Often defiant; shouting "no" becomes automatic.
Ritualistic; wants everything "just so"; routines carried out exactly as before; belongings placed "where they belong".[41]
Three-year-old
Physical
Growth is steady though slower than in first two years.
Adult height can be predicted from measurements of height at three years of age; males are approximately 53% of their adult height and females, 57%.
Legs grow faster than arms.
Circumference of head and chest is equal; head size is in better proportion to the body.
Produces verbs with "ing" endings; uses "-s" to indicate more than one; often puts "-s" on already pluralized forms: geeses, mices.
Indicates negatives by inserting "no" or "not" before a simple noun or verb phrase: "Not baby."
Answers "What are you doing?", "What is this?", and "Where?" questions dealing with familiar objects and events.[42][43]
Four-year-old
Physical development
Head circumference is usually not measured after age three.
Requires approximately 7,100 kJ (1,700 kcal) daily.
Hearing acuity can be assessed by child's correct usage of sounds and language, and also by the child's appropriate responses to questions and instructions.
Motor development
Walks a straight line (tape or chalk line on the floor).
Hops on one foot.
Pedals and steers a wheeled toy with confidence; turns corners, avoids obstacles and oncoming "traffic".
Climbs ladders, trees, playground equipment.
Jumps over objects 12 to 15 cm (5 to 6 in) high; lands with both feet together.
Runs, starts, stops, and moves around obstacles with ease.
Uses arm movement to increase running speed
Throws a ball overhand; distance and aim improving.
Builds a tower with ten or more blocks.
Forms shapes and objects out of clay: cookies, snakes and other simple animals.
Reproduces some shapes and letters.
Holds a crayon or marker using a tripod grasp.
Paints and draws with purpose; may have an idea in mind, but often has problems implementing it so calls the creation something else.
Becomes more accurate at hitting nails and pegs with hammer.
Threads small wooden beads on a string.
Can run in a circle
Can jump
Cognitive
Can recognize that certain words sound similar
Names eighteen to twenty uppercase letters. Writes several letters and sometimes their name.
A few children are beginning to read simple books, such as alphabet books with only a few words per page and many pictures.
Likes stories about how things grow and how things operate.
Produces elaborate sentence structures: "The cat ran under the house before I could see what color it was."
Speech is almost entirely intelligible.
Begins to use the past tense of verbs correctly: "Mommy closed the door", "Daddy went to work."
Refers to activities, events, objects, and people that are not present.
Changes tone of voice and sentence structure to adapt to listener's level of understanding: To baby brother, "Milk gone?" To Mother, "Did the baby drink all of his milk?"
States first and last name, gender, siblings' names, and sometimes own telephone number.
Answers appropriately when asked what to do if tired, cold, or hungry. Recites and sings simple songs and rhymes.
Social development
Outgoing; friendly; overly enthusiastic at times.
Moods change rapidly and unpredictably; laughing one minute, crying the next; may throw tantrum over minor frustrations (a block structure that will not balance); sulk over being left out.
Imaginary playmates or companions are common; holds conversations and shares strong emotions with this invisible friend.
Boasts, exaggerates, and "bends" the truth with made-up stories or claims of boldness; tests the limits with "bathroom" talk.
Cooperates with others; participates in group activities.
Shows pride in accomplishments; seeks frequent adult approval.
Often appears selfish; not always able to take turns or to understand taking turns under some conditions; tattles on other children.
Insists on trying to do things independently, but may get so frustrated as to verge on tantrums when problems arise: paint that drips, paper airplane that will not fold right.
Enjoys role-playing and make-believe activities.
Relies (most of the time) on verbal rather than physical aggression; may yell angrily rather than hit to make a point; threatens: "You can't come to my birthday party."
Name-calling and taunting are often used as ways of excluding other children.
Can be bossy at times, telling their parents to stop talking, or telling their friends to "Come here right now."
Establishes close relationships with playmates; beginning to have "best" friends.
Begins to ask questions about own and others' bodies[44]
May attempt to see others naked in the bathroom[44]
Middle childhood
Five-year-old
Physical
Head size is approximately that of an adult's.
May begin to lose "baby" (deciduous) teeth.
Body is adult-like in proportion.
Requires approximately 7,500 kJ (1,800 kcal) daily
Visual tracking and binocular vision are well developed.
Motor development
Walks backwards, toe to heel.
Walks unassisted up and down stairs, alternating feet.
May learn to turn somersaults (should be taught the right way in order to avoid injury).
Can touch toes without flexing knees.
Walks a balance beam.
Learns to skip using alternative feet.
Catches a ball thrown from 1 m (3.3 ft) away.
Rides a tricycle or wheeled toy with speed and skillful steering; some children learning to ride bicycles, usually with training wheels.
Jumps or hops forward ten times in a row without falling.
Balances on either foot with good control for ten seconds.
Builds three-dimensional structures with small cubes by copying from a picture or model.
Reproduces many shapes and letters: square, triangle, A, I, O, U, C, H, L, T.
Demonstrates fair control of pencil or marker; may begin to color within the lines.
Cuts on the line with scissors (not perfectly).
Hand dominance is fairly well established
Cognitive
Forms rectangle from two triangular cuts.
Builds steps with set of small blocks.
Understands concept of same shape, same size.
Sorts objects on the basis of two dimensions, such as color and form.
Sorts a variety of objects so that all things in the group have a single common feature (classification skill: all are food items or boats or animals).
Understands the concepts of smallest and shortest; places objects in order from shortest to tallest, smallest to largest.
Identifies objects with specified serial position: first, second, last.
Rote counts to 20 and above; many children count to 100.
Recognizes numerals from 1 to 10.
Understands the concepts of less than: "Which bowl has less water?"
Understands the terms dark, light, and early: "I got up early, before anyone else. It was still dark."
Relates clock time to daily schedule: "Time to turn on the TV when the little hand points to 5."
Some children can tell time on the hour: five o'clock, two o'clock.
Weight gains reflect significant increases in muscle mass.
Heart rate and respiratory rates are close to adults.
Body may appear lanky as through period of rapid growth.
Baby teeth beginning to be replaced by permanent ones, starting with the two lower front teeth
20/20 eyesight; if below 20/40 should see a professional.
The most common vision problem during middle childhood is myopia, or nearsightedness.[4]
Uses 6,700 to 7,100 kJ (1,600 to 1,700 kcal) a day.
Motor development
Gains greater control over large and fine motor skills; movements are more precise and deliberate, though some clumsiness persists.
Enjoys vigorous running, jumping, climbing, and throwing etc.
Has trouble staying still.
Span of attention increases; works at tasks for longer periods of time.
Can concentrate effort but not always consistently.
Understands time (today, tomorrow, yesterday) and simple motion (some things go faster than others).
Recognizes seasons and major activities done at certain times.
Has fun with problem solving and sorting activities like stacking, puzzles, and mazes
Enjoys the challenge of puzzles, counting and sorting activities, paper-and-pencil mazes, and games that involve matching letters and words with pictures.
Recognizes some words by sight; attempts to sound out words
In some cases the child may be reading well.
Functioning which facilitates learning to ride a bicycle, swim, swing a bat, or kick a ball.
Enjoys making things.
Reverses or confuses certain letters: b/d, p/g, g/q, t/f.
Able to trace objects.
Folds and cuts paper into simple shapes.
Can tie laces, string (like shoes).
Language
Can identify right and left hands fairly consistently.
Holds onto positive beliefs involving the unexplainable (magic or fantasy)
Arrives at some understanding about death and dying; expresses fear that parents may die.
Talks a lot.
Loves telling jokes and riddles; often, the humor is far from subtle.
Capable of basic gymnastics moves such as somersaults
Writing grips
The dynamic tripod grip is the final stage of holding writing implements
Language
Vocabulary now numbers at least a few thousand words
Capable of telling time
Begins to understand how sounds form words
Social and emotional
Highly self-critical and eager to please
Can understand right and wrong
Increased ability at problem solving and reasoning
Can feel shame and guilt
Complains a lot and has strong emotional swings
Occasionally has meltdowns over minor frustrations, mainly for attention
Ability to deal with mistakes and failure improves
Beginning of sexual attraction to/interest in peers[44]
Explore genitalia with other children their age. This occurrence typically begins with children "playing doctor" or who say "show me yours and I'll show mine." The event is the child showing interest in "naughty parts" which are perceived as forbidden[44]
Reluctant to undress in front of others and wish to have more privacy from parents[44]
Eight-year-old
Motor development
Has good finger control
Increased physical strength and endurance
Almost able to converse at an adult level
Wants to understand how and why things work
Clear, logical thinking skills
Exhibits a clear preference for certain subjects and activities
Language skills
Enjoys reading
Can start to understand how opposites work
Can now speak clearly
Social and emotional
Starts to develop a close circle of same-gender friends
May persist with a particular physical activity to the point of exhaustion
Language skills
Good at memorizing and recalling information, but typically does not show a deep understanding of it
Capable of concentrating and resuming a task after an interruption
Eager to learn skills
Starts to understand right vs wrong in place of good vs bad
Social skills
Often displays an intense revulsion of the opposite gender
Will use physical complaints as a means of getting out of undesired tasks
Generally dependable and can be trusted with basic responsibilities
Prone to wide mood swings
Ten-year-old
Motor skills
Capable of demanding motor/endurance tasks like bicycling and team sports
Some girls may begin puberty, starting with breast development and followed by a change in facial shape
Adult-like motor planning
Motor planning includes an individual's choice of movements and trajectory of such movements. Children begin to display motor planning in preference of certain body parts such as hand preference. For instance, left-handed children will start to plan how they can perform a motor skill, like throwing a ball, but execute it with their left hand. The preferred hand selection of children would also be displayed in other motor tasks.
Children show significant increase in sensitivity to end-state comfort (ESC)
ESC is the preference to initially use unusual uncomfortable postures and movements to end in a comfortable position. One common method of studying end-state comfort is the task of over-turned glass. In this task, individuals are asked to use one hand to pick up a drinking glass that is placed up-side down, turn it upright, and pour water from a given cup into the glass. Once the children begins to grab the upside-down glass with thumb pointing down, then they have displayed end-state comfort. As a result, once they have turned over the glass, the child would have ended with palm holding the glass in a comfortable position.
The number of grips conforming to ESC strongly increased with age.[45]
Language skills
Still does not display a deep understanding of subjects
Does not yet fully understand right from wrong
Not yet good at organizing or planning things in a practical way
Capable of categorizing information to make better sense of it. Reads adult books and magazines on subjects of interest. Capable of proofreading homework for spelling, grammar, and logic.
Social skills
Overall disposition is pleasant and upbeat. Can become extremely excited over subjects of interest or accomplishments. Strongly prone to peer pressure and following trends. More stable friendships with fewer melodramatics than at 11.
May begin to have sexual attraction to/interest in peers.
Thirteen years old
Menstruation in girls is common
Growth spurts, ejaculations and voice changes are common in boys, as well as "peach fuzz", small strands of facial hair above their lip along with fine underarm hair
Moody and uncomfortable with themselves and their surroundings
Likes to be alone and values privacy
May believe the world is out to get them
Insecure about their bodies
May not get along well with adults
Fourteen years old
Boys may begin growth of fine facial hair
Generally pleasant, sunny disposition
Often a high interest in extracurricular activities
May want to please and be popular
Has a large circle of both-gender friends
Fifteen years old
Typically argumentative and unwilling to share their problems with others
May want to be independent and free of their family
Typically gets along better with siblings than parents
Friendships are highly important
Romantic interests are common.
Many teenagers at this age are starting to drive with a learner's permit, allowing them to drive with someone else in the car.
Sixteen years old
Boys typically begin to grow thick facial hair
Good overall relationship with family
Begins to see parents as human beings instead of authority figures
Friendships highly important, may have a wide circle of both gender friends
Many teenagers at this age are starting to drive on their own.
^ abJim McMorran; Damian Crowther; Stew McMorran; Steve Youngmin; Ian Wacogne; Jon Pleat; Clive Prince. "Hand regard – General Practice Notebook". Gpnotebook.co.uk. Retrieved 28 April 2013.
^Trawick-Smith, J (2013) Early childhood development: a multicultural perspective. (6th Edition) USA: Pearson.
^Bertsch, C., Unger, H., Winkelmann, W., & Rosenbaum, D. (2004). Evaluation of early walking patterns from plantar pressure distribution measurements. First year results of 42 children. Gait & Posture, 19(3), 235. doi:10.1016/S0966-6362(03)00064-X
^Parten, M. (1932). "Social participation among pre-school children". The Journal of Abnormal and Social Psychology. 27 (3): 243–269. doi:10.1037/h0074524.
^Ruben, K. H., Fein, G. G., & Vandenberg, B. (1983). "Play", pp. 693–744 in E. M. Hetherington (Ed.), Handbook of child psychology: Vol. 4. Socialization, personality, and social development (4th ed.). New York: Wiley, ISBN0471090654.
^Harding, J. (2013) Child development: an illustrated handbook. Oxon: Hodder Education.
^Hobart, C. Frankel, J. and Walker, M. (2009). A practical guide to child observation and assessment. (4th Edition.) Cheltenham: Stanley Thornes Publishers
^Child development. Early Years Matters, Bury, UK (last accessed 12 March)
^Jovanovic, B; Schwarzer, G (2017). "The influence of grasping habits and object orientation on motor planning in children and adults". Developmental Psychobiology. 59 (8): 949–957. doi:10.1002/dev.21573. PMID29071707. S2CID23941550.
