Supporting young people’s successful transition to adulthood requires a clear understanding of the predictable stages of development. While every young person is an individual, with their own unique background, abilities, personal characteristics, life events and context, there are major developmental events that are common across young people and likely to occur in the transition from childhood to adulthood. The following is intended to provide practical, useable information about youth developmental milestones that can help identify the supports youth may need as they develop.

Understanding youth development

Ages and stages: about youth development

Youth development occurs uniquely for each individual

While there are a number of developmental events that are common to today’s youth, development is also affected by a multitude of individual factors. Some individuals will reach milestones at an early age, while others may take more time or might not reach certain milestones at all.

This resource outlines the progression of movement along developmental trajectories that are common for the majority of young people. It aims to help foster a common understanding of youth development and to cultivate interactions with young people that are positive and productive.

The developmental maps are not a "schedule" of development that follows a rigid timeline, nor do they represent the developmental trajectory of any individual youth.

From straight lines to circles

The developmental events presented in this section of the resource are packaged neatly into specific domains and age-specific segments to make the resource practical and easier to use. In reality, human growth is much more complex.

Figure 1 is a circle split into four equal parts in different colours. Each part represents the different developmental domains of human growth: cognitive (yellow, upper left quarter), emotional (green, upper right quarter), social (blue, lower left quarter) and physical (purple, lower right quarter)

The interrelated and interdependent nature of human development can be considered as a circle (Figure 1), in which growth in one domain impacts and is connected to the others (Simard, 2011; Ontario Federation of Indian Friendship Centres, 2011). As you move through the developmental maps featured later in this section, it is important to remember that maturation always takes place as part of the whole. Healthy development of the mind, body and spirit is—as our Aboriginal partners have long affirmed—contingent on balance and interconnectedness. It is also important, regardless of the age of the youth you serve, to familiarize yourself with the events that might have already taken place, and with those that may be arriving shortly. By having a perspective of the overall developmental picture, you can better anticipate and support the growth that is to come.

Figure 2 adds a blue ring around the circle of human development to show the importance of environment or context to youth development.

Context matters!

Throughout conversations with researchers, community leaders, and youth across the province about youth development, one message was clear: context matters (Figure 2). It matters whether a young person is growing up in an urban or rural setting, a high or low socio-economic status neighbourhood, in a minority setting for a Francophone, or in a particular cultural community, for example, one of the many Aboriginal communities in Ontario. Environment, history and life events impact the experiences youth have, the challenges they face, the supports and opportunities they have access to and the choices that they make.

Sense of self: a core concept

Many researchers, youth and community leaders told us that, despite all the rapid and significant changes that take place as a child becomes an adult, there remains an enduring (yet changing) core or sense of self in each person (Figure 3). It is this “force of gravity” that connects aspects of development and experience together. The concept of self takes on different meanings for different people. For example:

  • For some individuals of Aboriginal descent, the sense of self has a spiritual significance. Simard (2011) notes that “feeding the spirit is as equally important as feeding the body and both must be attended to in a caring manner”
  • The self may take on a cultural meaning. Francophone youth, for example, may perceive their French heritage and language as a central component of their core self
  • Some may consider their self to be religious in nature
  • There may even be some young people who pay little attention to their sense of self

Figure 3 adds an inner circle at the centre of the circle of human development to represent self or spirit within.

When thinking about the individual and contextual issues that influence youth development, it is important to keep this additional factor of self in mind. By acknowledging the core self, you can demonstrate sensitivity and greater understanding of a young person’s unique needs. And while the nature of a youth’s self may not be immediately apparent, the individual youth’s core self can often be discovered through discussion and attentive listening.

A young person’s sense of self can be a valuable platform for making youth development experiences relevant and engaging to them. It can also further their developmental growth (for example, identity formation, social group-esteem).

Engaging youth in a way that connects with their self should be done sensitively and thoughtfully. If you feel that you do not have the skills or knowledge, or feel comfortable, in engaging youth in this way, it can be helpful to seek out, and partner with, individuals (for example, elders, community leaders) or organizations that have this expertise.

This path or that?

We do not assume that there is a single path to success. Every person starts their journey from a unique position and may likewise be headed toward a unique destination. Individual attributes, life choices, and environmental factors interact to set a young person’s general direction in life. While some pathways may lead to more successful outcomes than others, this doesn’t imply that there is only one road to adulthood. A young person who is headed down one path can, with guidance and support, always chart a new course—this resource helps to provide a map.

An overview: adolescence and early adulthood

Adolescence is a period of rapid change

Adolescents and young adults experience many changes, often occurring simultaneously or in rapid succession. Beginning with puberty, youth undergo major physical changes at the same time that:

  • their capacities for thinking and reasoning begin to mature
  • their emotional responses become more intense
  • their social worlds expand as peer groups become more important and romantic relationships begin

While negotiating these changes, young people also grapple with their emerging identities, make important decisions about the future, and face a number of transitions:

  • into and out of high school
  • into post-secondary education and/or the job market
  • reaching legal driving age and then legal adulthood
  • leaving their family home and establishing independence
Four dimensions of development

The developmental maps presented later in this section of the resource are organized across the cognitive, emotional, social, and physical aspects of youth development. A brief description is provided in the following pages to highlight the key features of each of these domains.

Cognitive development

Changes in the brain

The brain continues to adapt beyond the early years

As recently as the mid-1990s, the prevailing belief among neuroscientists was that the more important aspects of brain development ended by about age three. We now know that the brain continues to organize, adapt and change well beyond the early years. In fact, the changes that occur in the brain during late childhood, adolescence and young adulthood are particularly dramatic (Jetha & Segalowitz, 2011).

Brain function becomes increasingly efficient and specialized

The human brain reaches adult size just before puberty (around age 12). In several regions of the brain, grey matter (neurons or brain cells) increases until the onset of puberty and then decreases as neurons are eliminated through a “use it or lose it” process. This process contributes to the increasing efficiency of brain functioning during adolescence and to adolescents’ increasing ability to process complex information and learn new concepts. At the same time, white matter (myelin and axons) increases, speeding up the rate of signals moving between brain cells, also contributing to the brain’s increasing efficiency.

The “executive” functions slowly mature

The area of greatest change after puberty is the prefrontal cortex. This area is associated with “executive” functions such as monitoring, organizing, planning, decision making, anticipating consequences, impulse control, and delay of gratification. The maturation of the prefrontal cortex is a slow process that takes place throughout adolescence and early adulthood. This maturation process depends to a large degree on experience—the executive functions are acquired and develop through practice. The resources and variety of experiences available to adolescents and young adults, as well as the ways in which they decide to spend their time, contribute to variability across individuals in terms of their brain development.

Processing and reasoning skills

Processing speed, concentration and memory improve

Processing speed (how quickly new information is taken in) increases until mid-adolescence. Adolescents become gradually better at ignoring irrelevant information in order to concentrate on information relevant to the task at hand. Young people also get steadily better at replacing an already-established response when a new and different response is required. In addition, working memory and the ability to multitask improve throughout adolescence and into adulthood.

Reasoning abilities improve

These improving capacities are accompanied by improvements in reasoning abilities. The ability to think abstractly develops during adolescence, as does the ability to think logically, and consider different perspectives. Youth also become more able to engage in scientific reasoning to formulate and test hypotheses and draw conclusions.


Young children tend to have a difficult time separating their perspective from others’ perspectives, or understanding that others may have a different perspective on a given situation or issue.

In adolescence, the young person can come to understand that other people may hold different perspectives and that those people appreciate different perspectives themselves (this is called “mutual perspective-taking”). By late adolescence, young people can come to understand how these mutual perspectives are influenced by people’s social roles. This developmental progression is not tightly linked with age. For example, while many young adolescents are capable of mutual perspective-taking, it is not uncommon to find late adolescents who are not capable of it.

Perspective-taking on its own is not sufficient. Without the emotional capacity for empathy, for example, a person can take advantage of others with the knowledge gained from their perspective-taking abilities.

Learning strategies improve

Learning strategies generally improve throughout adolescence and into adulthood. Adolescents are able to reflect on their own thinking, and they are able to observe how they learn and develop strategies to improve their learning.

Learning and the influence of digital media

Digital media may have influenced adolescent learning styles

Some researchers believe that digital media and communication technologies have had a profound impact on the learning styles and behaviours of today’s youth (Martinovic, Freiman & Karadag, 2011). These youth:

  • prefer receiving information quickly
  • are adept at processing information rapidly
  • prefer multi-tasking and non-linear access to information
  • are kinaesthetic, experiential, hands-on learners who are most easily engaged with first-person learning, games, simulations, and role-playing (Junco and Mastrodicasa, 2007; Oblinger and Oblinger, 2005; Tapscott, 2009)

They also rely heavily on communication technologies to access information and to carry out social and professional interactions (Veen & Vrakking, 2006; Pletka, 2007).

Beliefs about knowledge

Adolescents develop a more rational approach to knowledge

As well as reflecting on their own thinking, adolescents begin to think about knowledge and the trustworthiness of different knowledge claims. Some adolescents may become skeptical of all claims, while others may accept the knowledge claims of a single authoritative source and reject all others.

With further development, adolescents and young adults can move toward a more rational approach to knowledge in which it is accepted that not all claims are equally true (or untrue), and that, by considering evidence and arguments, it is possible to discern that some claims are more likely to be true than others.

Supporting cognitive development

Youth told us that they want a reasonable level of support to help keep their lives in order. They want friendly reminders about upcoming commitments and tell us, for example, that they are keen to receive instruction on how to use a “to do” calendar or agenda. When deadlines or obligations are missed (due to a conflict with a friend, for example), most adolescents are looking for their adult allies to show some understanding. But, as these skills develop, young adults say they are comfortable receiving less direct prompts and want to be held more accountable.

When faced with significant life decisions, like which career path to follow, most youth said that they are interested in hearing about, and discussing, the experiences and first-hand knowledge of others. Youth also mentioned the importance of having many adults in their lives as a way to increase exposure to a variety of different perspectives (for example, cultural activities, social perspectives). At the same time, young people told us they ultimately desire the freedom to make decisions for themselves.

Emotional development

Experiencing emotions

Emotion, motivation and stress are heightened

Adolescents often feel emotions more intensely, and are more sensitive to pleasure and reward than either children or adults. In addition, adolescents are often particularly vulnerable to stress.

Adolescents are less able to regulate their desires and emotions

Adolescents are not as able as adults to curb their desire for pleasure, which can lead to an increase in risk-taking behaviour. Adolescents are also not as able as adults to manage their emotions and their stress levels, which leaves adolescents more vulnerable to mental health issues. In fact, the lifetime risk for the emergence of mental disorders (for example, anxiety, depression) peaks in adolescence.

Although risk-taking behaviour is often associated with negative outcomes (such as car accidents or addictions), the curiosity and desire for novel experiences that fuel risk-taking also present tremendous opportunities for exploration, learning and development. Learning to become independent, for example, is a very risky endeavour, but it is a key part of adolescence.

Emotional regulation

Learning to manage emotions is a key task in adolescence

The key developmental task for youth in the emotional domain is the development of emotional self-regulation. While adolescents have become more capable of experiencing emotions, their capacity for self-regulation and for decision making lags behind. Learning to regulate their emotions is, therefore, initially quite difficult for adolescents.

Strategies for emotional regulation broaden and shift from primarily external, behaviourally-oriented strategies in childhood (when parents and other significant adults help children regulate their emotions) to more internal and cognitive (thought-based) strategies in adolescence and young adulthood, when it becomes important to regulate emotions independently.

Adolescents develop new adaptive strategies

Some of the cognitive strategies that emerge in adolescence work well for emotional self-regulation and are considered to be “adaptive” strategies:

  • redefining or reframing a potentially emotional situation so that its emotional impact is lessened (cognitive reappraisal)
  • thinking about joyful and pleasant issues rather than the source of an emotional response (positive refocusing)
  • replacing negative thoughts or attributions about an emotional event/issue with positive ones (positive reappraisal)
  • putting things into perspective
  • acceptance
They may also use maladaptive strategies

Other strategies tend to be less successful in helping to regulate emotions in a productive manner. These maladaptive strategies include:

  • thinking repeatedly about the feelings and thoughts associated with a negative event, often involuntarily (rumination)
  • blaming oneself for the negative emotions experienced (self-blame)
  • blaming others
  • inhibiting behaviour that expresses emotions (expressive suppression)
Self-regulation is a critical success factor for adolescents

Adaptive emotional regulation is one of the factors that contributes to the ability to successfully cope and adapt to significant life stress or adversity. In adolescence, adaptive emotional regulation strategies are associated with maintaining good social relationships, academic achievement, and overall psychological well-being. Maladaptive emotional regulation, on the other hand, is associated with poorer mental health outcomes. In young adulthood, adaptive emotional regulation is associated with more positive outcomes in areas related to memory, relationships, and responses to stressful life events.


Empathy develops late in adolescence

Empathy—the capacity to recognize and share emotions that another person is experiencing—does not generally become fully developed until early adulthood. In childhood, a rudimentary form of empathy emerges when children start to feel distressed while observing someone else’s emotional distress. In late childhood and early adolescence, this distress is replaced by empathy when young people recognize the distinction between their own and others’ emotional reactions. Empathy during adolescence involves a largely emotional response, while mature empathy that emerges in early adulthood involves a more cognitive evaluation of the other person’s emotional response.


Motivation becomes increasingly internalized

In early adolescence, motivations for engaging in behaviour begin to shift from extrinsic to intrinsic. When extrinsically motivated, individuals engage in activities for external reasons (for example, to earn a reward or avoid punishment). When individuals are intrinsically motivated, they engage in an activity because they are interested in and realize the benefits of the activity.

While tasks such as homework and housework do not generally become intrinsically motivated (few people enjoy these tasks in and of themselves), reasons for engaging in such tasks start to become internalized in early adolescence. For example, adolescents start doing their homework of their own accord—rather than at the insistence of their parents—because they have internalized reasons for doing so (for example, they want to earn good grades). The internalization of motivations continues to develop throughout adolescence as behaviour becomes more self-regulated.

Supporting emotional development

As young people develop the skills to manage new and intense emotions, they tell us they often look to sources such as friends, family, teachers, and counsellors for comfort and support. When expressing their emotions, adolescents expect to have their feelings respected and validated, and they feel patronized when others downplay their emotions with statements like “it can’t be that bad” or “get over it, already”. Even as young people become more adept at managing their emotions, it is important to remember that we all need someone to talk to, from time to time.

Young people, while acknowledging an affinity for excitement and risk-taking, expressed a desire to take these risks in a safe environment. A class trip to a rock-climbing gym, for example, was suggested by one youth as an effective means of safely seeking thrills. Youth were also adamant that they need information and advice on the potential impacts of risky behaviours so that they are better prepared to make good decisions. They reported that access to objective, frank information is especially crucial for young adults, who are often making decisions in an unsupervised setting.

Social development

Social development concerns identity, relationships, and moral capacity

Adolescents develop a sense of self identity that carries into early adulthood. Identity development can include many different components such as gender identity, social group identity (particularly for youth in minority groups), and spiritual identity. While maintaining their sense of self, youth have to develop a capacity for intimate relationships with their peers and romantic partners, while developing independence from their parents. In order to successfully manage their relationships with others, young people also have to develop successful strategies for addressing moral issues (Côté, 2011).

Self development and identity formation

Most adolescents will explore varied identities

Early adolescents typically delay in making any identity commitments. As they mature, most will actively explore different identity options (for example, information about various career options). Many will start to question their parents’ values as they consider their own values. Others may skip the identity exploration phase and commit to identity roles based on the expectations of others (for example, allowing their parents to decide on future career direction).

After a sometimes prolonged period of exploring who they are and how they fit into the world, adolescents and young adults generally begin committing to an identity that includes roles, values, beliefs and goals. Identity development includes several different components, such as self-concepts, self-efficacy, and self-esteem.


Self development begins with the emergence of self-concepts. In childhood, these self-concepts tend to be quite concrete (for example, I live in Canada, I have a dog, I want to be a fireman when I grow up). In early adolescence, self-concepts become more abstract (I am a leader, I am ambitious, I am spiritual) and more specific to each individual.

Later in adolescence, self-concepts become more differentiated across different contexts (for example, one individual may be deferential with parents, a leader among friends and shy in class), and adolescents also start to notice some conflicts in their conceptions of themselves in different situations. These conflicting self-concepts can provoke anxiety as adolescents try to work out who they really are.


Self-efficacy involves a person’s appraisal of their own ability to organize and execute a course of action to attain a set goal. Self-appraisal skills begin to improve in early adolescence (for example, mistaken childhood beliefs of competence are replaced by realistic assessments of skill level) and early adolescents also begin to engage in social comparison (comparing their skill levels to those of their peers). As a result, self-efficacy often declines in early adolescence. Young people, especially girls, become less certain of their ability to achieve goals. The decline often continues into mid-adolescence at which point self-efficacy begins to increase.


Self-esteem is a more general opinion of one’s own personal worth. In contrast to self-efficacy, which is based on judgments of one’s abilities in particular domains, self-esteem is based on emotional responses—how individuals feel about themselves. Self-esteem tends to decline in early adolescence (especially among girls) and often continues to decline into early adulthood at which point it begins to rise again and continues on an upward trend throughout adulthood until old age.

Gender identity

The development of gender identity shifts in early adolescence when gender role stereotypes start to intensify. Early adolescents often become more attentive to, and strict about, gender stereotypes. This often changes later in adolescence when youth tend to become less rigid about what is appropriate for men and women and begin to reject gender stereotypes.

Social group identity also expands

Social group identity also begins to shift in early adolescence. Early adolescents (particularly those from minority groups) begin to show an increase in social group-esteem (they show increasing pride in belonging to their own social group). This increase continues through adolescence and into early adulthood. By early adulthood, many youth will have achieved a defined social group identity. They display a commitment or sense of belonging to the group; they feel comfortable with their own social identity; and, after independent examination of their own beliefs, they reject the negative views held by others based on stereotypes about their social groups.

Spiritual identity

Spiritual/religious identity is another aspect of identity that may begin to shift in early adolescence—adolescents may start to question and explore the foundations of the religious or spiritual beliefs they have previously held. Young adults may integrate their religious or spiritual beliefs into their larger identity or, in other cases, religious/spiritual beliefs may be abandoned.

Development of relationships

Developments in perspective-taking and the growing importance of peers carry important implications for social development during adolescence.

The ability to appreciate varied perspectives emerges

Children learn at a young age to understand that others can have different perspectives than their own (for example, they can hold different beliefs and have different desires) but the development of perspective-taking continues into early adulthood. Later in adolescence, young people begin to understand that perspectives are almost never “neutral” and that everyone’s perspective is coloured by their context, beliefs and background.

This facilitates deeper peer relationships

These changes in perspective-taking allow for the establishment of deeper bonds of intimacy between peers and romantic partners. In early adolescence, input from peers starts to become more important and young people start making social comparisons with their peers, comparing their abilities and popularity, for example. At the same time, young people become more self-conscious (especially in the presence of their peers) and more vulnerable to peer pressure.

Romantic relationships may emerge

In early adolescence, an interest in romantic relationships begins to emerge, although mainly within the larger peer group. Early adolescents become interested in romance and start to experience passionate feelings. They may begin to form mixed-gender friendship groups and time spent with romantically attractive peers usually occurs within the context of those groups. For lesbian, gay, bisexual, transgendered, two-spirited and queer (LGBTTQ) youth, an early awareness of sexual orientation may be forming and LGBTTQ youth may feel some apprehension regarding their same-sex attractions due to social stigma (Scott & Walsh, 2011).

Later in adolescence, young people begin experiencing their earliest romantic relationships. These early romantic relationships are usually not based on emotional intimacy but more often are about fun and camaraderie, although some expressions of emotional intimacy may begin to emerge, and sexual behaviour may progress. LGBTTQ youth often acknowledge and may disclose their sexual orientation (“come out”) in mid-adolescence. They may tell a trusted friend or family member about a same-sex romantic interest.

In early adulthood, the focus within romantic relationships shifts to forming strong emotional and intimate bonds with a compatible partner. For many youth, it can be challenging to form close connections with a romantic partner while still maintaining a separate sense of identity. LGBTTQ youth often have their first openly same-sex relationships in early adulthood.

Parent relationships may suffer

As adolescents devote more of their time and energy to their peer and romantic relationships, their relationships with parents can suffer a period of heightened conflict. While frequent, high-intensity, angry fighting is not necessarily a feature of adolescence, the frequency of day-to-day conflicts over matters—both large and small—often grows. Conflict with parents tends to be most frequent in early to mid-adolescence, and generally declines afterwards.

Supporting social development

Young people said that exposure to different art forms and cultural ceremonies, travelling abroad and volunteering were some of the opportunities which shaped “who they are”. During this period of exploration, young people told us that freedom to discover their identity and to express their individuality is crucial but also note that they can be conscious of judgement, criticism and rejection from others. Youth advised that it is important for adult allies to keep an open mind. This will not only help youth feel comfortable as they grow, but also fosters the quality of relationships they learn to build with adults.

Peers, family members, and community leaders, as well as contemporary and historical figures, were all mentioned by youth as strong influencers of their sense of identity. Having access to positive role models, youth emphasize, is a critical ingredient in identity formation and positive development. Young people also told us that, because they are constantly observing, learning and emulating, positive role models can help them behave in positive and productive ways.

Physical development

Physical activity

Strength and endurance

Throughout adolescence and into young adulthood, young people will notice changes in their cardiovascular endurance, muscle strength and endurance, and flexibility. These changes depend on the levels of physical activity in which young people engage. In general, there is a decline in physical activity beginning around age 13 and continuing into adulthood.

Identifying physical strengths and limitations

In early adolescence, many young people will become aware of their physical strengths and limitations. Many young people will use this information to make decisions about the activities they will engage in into adulthood—often giving up sports they previously enjoyed and concentrating on those at which they excel (Lu, 2011).

Changes in the body

Sleep patterns

The physical changes of puberty are also associated with changes in adolescents’ sleep patterns. Adolescents feel wide awake and alert until late at night, and have difficulty waking up early in the morning. Sleep deprivation can be a consequence. It can contribute to moodiness and irritability as well as difficulties in cognitive processing and emotional regulation (Wolfson & Carskadon, 2003).

Puberty signals the onset of many physical changes

Much of the physical development that takes place during adolescence begins with puberty. These changes include a growth spurt marking the onset of adolescence. Females typically have their growth spurt around age ten, males around age twelve. Puberty also brings the development of primary and secondary sexual characteristics.

Body image

These marked changes to the body and mind have significant impacts on how youth feel about the appearance of their body. Females, whose body mass tends to increase during puberty, may develop a negative body image. This can affect their mood, eating habits and mental well-being. Males, on the other hand, tend to put on muscle mass, start to develop a masculine shape and generally become more satisfied with their physical appearance (Hayword, 2003).

Regardless of a young person’s sex, when puberty begins exceptionally early or late, there may be a greater likelihood of body image dissatisfaction (Hayword, 2003).

Nutritional requirements

The nutritional requirements for healthy development will also increase around the onset of puberty. Caloric intake, especially during a growth spurt, can skyrocket. The body’s need for protein increases too, as it builds muscle mass. Calcium, the mineral required to build bones, is also very critical during the adolescent years (Spear, 2002).

As youth spend more time outside the family home, their eating habits often become chaotic. They begin to skip meals (often breakfast) and eat while on the go. An increasing portion of a young person’s food energy comes from habitual snacking between solid meals.

Supporting physical development

Youth tell us that leading a healthy and active lifestyle is a high priority but many obstacles make this difficult. Because their lives are filled with competing concerns, young people reported convenience as a significant factor. Recreation during the lunch hour was cited as an attractive option as were activities in accessible locations.

Variety is also crucial to attracting and maintaining participants’ interest. Some noted that activities were overly competitive, and required too large a commitment of time and resources. The option to try non-traditional activities like hiking or yoga, youth said, would also go a long way in encouraging healthy living.

Additionally, adolescents highlighted a desire to organize their own recreational initiatives. Youth report that such opportunities are valuable on two fronts: the youth organizers develop a range of valuable competencies (for example, self-efficacy, building relationships); and participants profit from their exposure to positive youth role models in a constructive setting.