Developing physically, for example, changes the ways in which children are able to coordinate their gross-motor skills. Increased mobility opens up new ways to use toys. A higher level of fine-motor skill permits greater manipulation of objects. Ultimately, such knowledge helps to identify and distinguish the characteristics of toys that are appealing to children at a given age.

Although information of this sort is noted throughout the guidelines in relation to a specific subcategory of toys, this section summarizes typical play behaviors regardless of the toy used, and identifies appropriate and appealing toy characteristics that are generally consistent among all subcategories of toys. With this information, the reader will be better able to make an age determination for a given toy, even if that toy is not specifically addressed within the guidelines.

Object play is limited during this period since learning occurs mostly through the reflexive actions of the child, such as spontaneous kicking or arm movements. Initially, they explore with their eyes and ears only. Newborns can focus best at about eight inches from their faces, but this increases over time and they may be able to see objects several feet away by the end of this period. Play objects should fit within their visual field at these distances. They are attracted to bright and vibrant colors, especially yellows and reds, and to objects with high-contrast patterns like black and white spirals. These children prefer the human face to all other patterns, and will watch faces intently. They will turn their heads in the direction of a sound, and are more attracted to objects that emit a gentle, soothing sound and that move slowly than to those that remain still or are too loud, too sudden, or otherwise extreme. Much of these infants' play involves watching and exploring their own body. They have a reflexive grasp, which only allows them to explore objects briefly, and at 3 months they begin to swipe or reach towards a dangling object to grasp it. Any object grasped is likely to be mouthed and to be handled with jerky, unpredictable motions. Therefore, soft, lightweight, washable, easy-to-grip objects with rounded corners are best. They start to learn and enjoy toys for which simple actions produce a clear, direct effect; for example, toys that light up, move, or create sound as a result of simple kicking or shaking.

Brightly colored and patterned toys that make gentle sounds are both appealing and appropriate for these children. Mobiles or images with bright, highly contrasting colors and patterns are appealing, as are mirrors.

Children now actively engage with their environments in systematic ways. Distance vision is more mature, and these children can track moving objects with smooth, efficient eye movements.

Bright colors, high contrasts, and complex patterns continue to be appealing. These children learn to differentiate among objects, as evidenced by their ability to group visual stimuli into categories. By 5 months of age, children can roll onto their backs and push up onto their hands and knees, so mobiles and suspended gyms are no longer appropriate at this age. They have mastered the ability to grasp and manipulate a dangling object by 6 months, and begin to engage in more active play by reaching, grasping, tugging, pushing, patting, shaking, and squeezing objects. At 6 to 7 months, children are sitting independently, which provides them with greater visual capacities for grasping objects or bringing objects to midline for exploration. They can manipulate objects more readily, though their fine-motor coordination is still rudimentary.

Objects are grasped using a claw-like grip or raking motion rather than a pincer grasp (i.e., using the thumb and index finger). They can transfer an object from hand to hand, and begin to use both hands independently; for example, one hand may hold an object while the other hand manipulates it. These children continue to mouth objects, so suitable toys are washable.

Near the end of this period, infants develop the ability to recognize oft-repeated words, and some are beginning to crawl and stand with support. At this time, they are also beginning to understand object permanence - that an object that is hidden or partially hidden did not actually disappear, but still exists somewhere. Soft, lightweight, rounded, and textured toys that make gentle sounds are appropriate. Hand-held objects, like simple musical toys, should be sized so these children can easily grasp and manipulate them. Books and images with bright pictures and high-contrast images are appealing, as are mirrors.

Much of the play during this period focuses on developing gross-motor skills as these children exhibit more outwardly oriented movements and become increasingly mobile. They can crawl forward and backward, pull themselves into a standing position, walk with support (for example, along furniture), stand momentarily without support, and complete a couple of unassisted steps.

They also begin to climb. These children explore objects in many different ways such as through grasping, shaking, squeezing, throwing, dropping, passing from hand to hand, and banging.

Although they can hold two objects and bang them together, they cannot coordinate the movements of both to use them together. They begin to develop a pincer grasp, which is used to pick up small objects between the thumb and fingers. Patterns of exploratory play begin that suggest older infants can make inferences about novel objects. For example, these children may infer what functions may operate beneath the surface of an object. They explore objects from every angle, and this often involves mouthing. Therefore, suitable toys are washable.

Many of these infants begin to use items in typical relational patterns; for example, dumping items out of a container, putting them back in, and then repeating the process. They repeat pleasurable actions often, and start to show an interest in marking on paper. Basic memory skills are developing and object permanence becomes more entrenched. When a toy is hidden or not within view, these children know the toy still exists and did not simply disappear. Infants of this age can understand simple words related to their immediate context, and need repetition and reinforcement of the words they hear. At the end of this period, these children begin to imitate gestures and the use of products. Sensory toys are highly appealing because these children are beginning to understand simple cause-and-effect relationships. Bright colors, especially yellows and reds, continue their appeal for this age group, as do high contrasts and complex patterns.

Pictures that represent familiar objects are also highly appealing. Suitable toys are soft, sturdy, have rounded edges, and are easily grasped or manipulated by the child.

Increasingly, these children can walk without support. However, they are still unsteady on their feet and their walking resembles toddling more than mature heel-to-toe walking. Now they want to explore everything; though their curiosity far outweighs their judgment for predicting outcomes or foreseeing dangers. They are trying out a variety of basic gross- and fine-motor skills, and are gaining confidence as climbers. They can sing to themselves and will move their bodies to music. Since they are more mobile, they can self-select toys that were once outside their reach. They find basic grasping easier, and can manipulate toys that require simple twisting, turning, sliding, and cranking. Through trial and error, they continue to explore cause-and-effect relationships like dumping and filling activities, and now they enjoy a variety of actions with objects, such as pressing, pushing, pulling, rolling, pounding, beating, clanging, fitting (for example, fitting a round peg into a round hole), stacking, marking, scribbling, carrying, and poking their fingers into objects. They delight in the many effects their actions cause, and enjoy toys that take advantage of this by the use of, for example, various sounds, blinking lights, and spinning wheels.

Children of this age can recognize the names of familiar people, objects, pictures, and body parts. Long-term memory and the development of simple vocabulary using one-word utterances now provide the foundation for make-believe or pretend play, however these children do not make clear symbolic connections until about 18 months of age. These children often imitate common actions they see - such as talking on the phone, "drinking" from a bottle or cup, or putting on a hat - but only in brief, sporadic episodes. They can defer imitating something for up to a week, and can also do so across a change in context (for example, away from home).

Simple toys that encourage pretend play, such as dress-up materials, dolls, stuffed animals, and small vehicle toys, are appropriate.

These children are more confident and stable at walking, and are exploring other skills such as balancing, jumping, and running. They can pull a toy behind them while walking, climb on and off furniture without assistance, walk up and down stairs with assistance, and - by the end of this period - may be able to kick a ball. They can now pick up and manipulate much smaller objects due to their more developed pincer grasp. They like to sort objects, often grouping them into two categories, and can now fit together simple objects. These children can match angles, which allows them to fit a square peg into a square hole. They can also start to use very simple coupling mechanisms like magnets, large hooks, and hook-and-loop or touch fasteners.

Representational and symbolic thinking emerges during this time frame, and children understand that some toys represent other objects. Representational art, however, is still in its infancy and may seem nonrepresentational to adults. Most of their artistic forays take the form of gestures, or a series of dots may represent, for example, a rabbit hopping. They can use simple phrases, a few active verbs, and directional words, such as "up," "down," and "in." Social play also emerges because children of this age can now communicate with and play alongside each other.

Rudimentary pretend and role-play emerge; these toddlers can pretend to be asleep and can role play a variety of commonly observed actions. As they approach 2 years of age, they may make dolls or stuffed animals assume roles, expecting them to eat pretend food. Though they still use trial and error, these toddlers can mentally consider solutions to problems before taking any action. This means they can remember and work with mental representations of familiar objects, pictures, letters, and numbers as they ponder appropriate actions. They are more goal-oriented and object permanence is more advanced. These children can help dress or undress themselves.

Toys with low to moderate cause-and-effect features - such as those with push buttons or pull cords that cause actions or sounds - are appealing to these children. Simple remote controls are also usable.

Now that pretend play is established, 2-year-olds can perform social roles like mommy, daddy, or baby. Role taking becomes a bigger part of social pretend play, and their pretend play becomes more elaborate as they use a variety of objects to carry out longer episodes. These children need the object to resemble the real item to some degree, so they might use a cloth rather than a shoe to represent a pillow. Two-year-olds can now engage in true construction play.

They understand that pictures can depict pretend objects, and scribbles gradually become more representational pictures during this period, though they are still more interested in the process than the product. They become increasingly interested in color variations and using simple art materials. Children at this age begin to show an interest in television and television characters.

They are drawn to familiar cartoon characters from shows that they can incorporate into their play themes. They often want to know "why," and can start to use simple learning or educational toys. They understand the purpose of numbers in counting objects.

Toddlers have increasing control over basic gross- and fine-motor skills. Interest in gross-motor activity increases with newly found physical strength and basic coordination, and they especially enjoy balancing, climbing, running, jumping, throwing, catching, playing with sand, or pushing and pulling wheeled objects. They learn these skills separately during this period, and with each passing year they gradually combine them with other skills as coordinated movement. They can perform somersaults, and like to dance, twirl, and gallop to music. Although their control is still uncertain, they can kick and throw a ball. They can manage simple screwing actions, and can use simple one- or two-turn wind-up mechanisms provided they are of low tension. Smaller buttons or snaps may be difficult for these children to manipulate, but they can use large hooks, buttons, and buckles. They prefer more realistic toys, so colors other than bright primary colors (for example, pastels) become attractive. However, these toys do not need to be elaborately detailed.

These children are entering the time of peak pretend play, and like to use replica objects as the actors in themes they sequence. A doll, for example, might be prepared to attend a birthday party with her doll friends, and they will drive in a car, eat food, and play chase or dance at the party.

Realistic props, like a realistic toy telephone, enhance pretend play at this age, but these children also start to use objects that are unlike the real item, so they might use a shoe to represent a pillow. They show greater interest in structured games. Gender preferences also become more evident. Girls typically choose dolls, household props, dress-up activities, and art materials, while boys tend to play more with blocks and small vehicle toys, and will engage in more aggressive or rough-and-tumble play.

These children progress considerably in their gross-motor skills. They can tiptoe and balance on one foot, hop, climb and slide on play structures with ease, kick or catch a large ball thrown from a short distance, and throw and aim at short distances. For example, they can now put a ball in a basket or target from 4 to 5 feet away. They now have the fine-motor skills to take on the challenge of more complex construction play, piecing together smaller puzzle pieces, cutting, pasting, and other art activities. Children at this age are still interested in different ways of manipulating a given art medium and learning about its properties, rather than creating a finished product. They start using lines to represent boundaries; this fosters the ability to draw people.

Drama and pretend play are at their zenith. These children like to invent complex and dramatic make-believe scenarios. They can build upon each other's play themes, create and coordinate several roles in an elaborate scenario, and better understand story lines. Many of these children still have difficulty understanding the differences between fantasy and reality. For example, children of this age may believe that monsters are real. They enjoy stepping into roles of power, like a parent, doctor, policeman, lion, or superhero, which helps them to better understand these roles, to make them less scary, or to fulfill wishes and express a broad range of emotions. As their cognitive and fine-motor skills improve, they begin to desire objects with more realistic detail, yet they still are not very concerned about mirroring reality.

These children further master gross- and fine-motor skills. They enjoy frequent trips outside to run, climb, hop, skip, and chase. They are learning to ride small bicycles, first with and then without training wheels. They are much more able to cut with scissors, paste, trace, draw, color, and string beads than 3-year-olds. They also have enough dexterity and coordination to start using a computer keyboard.

These children continue their interest in physical play outdoors, seeking to master more specialized physical skills. They are much stronger, have greater endurance, and are ready for more challenges. Their play includes more rough-and-tumble or risk-taking behaviors. They focus more on playing their games and activities by spontaneous or set rules, either of which can be complex. Common games outside include hide and seek, tag, and sports of all kinds. They often want to focus on and develop specific skills, and are adept at a variety of activities requiring great dexterity, such as complex hand games, jacks, snapping fingers, tying a bow, constructing models, operating hand puppets, needlepoint, sewing, weaving, and braiding. They can make small, controlled marks or movements while drawing or writing. They pay much more attention to detail, which facilitates a desire for collecting. At this stage they start using logic more often to solve problems, organize, or choose from a variety of alternatives. Their appreciation for simple jokes and riddles grows during this period. Licensed characters based on action superhero themes or friendship themes are very popular early on with this age group.

Children during this period continue to develop their skills at many of the sports, games, and activities from their early elementary years, however, some games become predictable and boring. Therefore, they are looking for a new range of activities to challenge their more advanced motor skills and thinking. Instead of finished products, they often prefer raw materials for creating their own unique products. These children enjoy a variety of activities at a more complex, exacting level of performance, such as woodworking, manipulating marionettes, making pottery, staging plays, advanced science projects, and generating computer graphics.

They are beginning a stage where they seek to clarify and express more complex concepts, moving from the concrete to the abstract and applying general principles to the particular.