Required Reading for Week 5 – HDFS 1500 Spring 2025

What you’ll learn to do: describe the physical changes that occur during puberty and adolescence

Physical changes of puberty mark the onset of adolescence (Lerner & Steinberg, 2009). For both boys and girls, these changes include a growth spurt in height, growth of pubic and underarm hair, and skin changes (e.g., pimples). Boys also experience growth in facial hair and a deepening of their voice. Girls experience breast development and begin menstruating. These pubertal changes are driven by hormones, particularly an increase in testosterone for boys and estrogen for girls. The physical changes that occur during adolescence are greater than those of any other time of life, with the exception of infancy. In some ways, however, the changes in adolescence are more dramatic than those that occur in infancy—unlike infants, adolescents are aware of the changes that are taking place and of what the changes mean. In this section, you will learn about the pubertal changes in body size, proportions, and sexual maturity, the social and emotional attitudes and reactions toward puberty, and some of the health concerns during adolescence, including eating disorders.

Physical Development during Adolescence

Puberty Begins

Puberty is the period of rapid growth and sexual development that begins in adolescence and starts at some point between ages 8 and 14. While the sequence of physical changes in puberty is predictable, the onset and pace of puberty vary widely. Every person’s individual timetable for puberty is different and is primarily influenced by heredity; however environmental factors—such as diet and exercise—also exert some influence.

Adolescence has evolved historically, with evidence indicating that this stage is lengthening as individuals start puberty earlier and transition to adulthood later than in the past. Puberty today begins, on average, at age 10–11 years for girls and 11–12 years for boys. This average age of onset has decreased gradually over time since the 19th century by 3–4 months per decade, which has been attributed to a range of factors including better nutrition, obesity, increased father absence, and other environmental factors (Steinberg, 2013). ^[1] Completion of formal education, financial independence from parents, marriage, and parenthood have all been markers of the end of adolescence and beginning of adulthood, and all of these transitions happen, on average, later now than in the past. In fact, the prolonging of adolescence has prompted the introduction of a new developmental period called emerging adulthood that captures these developmental changes out of adolescence and into adulthood, occurring from approximately ages 18 to 29 (Arnett, 2000). ^[2] We’ll learn more about this phase in the next module on early adulthood.

Hormonal Changes

Puberty involves distinctive physiological changes in an individual’s height, weight, body composition, and circulatory and respiratory systems, and during this time, both the adrenal glands and sex glands mature. These changes are largely influenced by hormonal activity. Many hormones contribute to the beginning of puberty, but most notably a major rush of estrogen for girls and testosterone for boys. Hormones play an organizational role (priming the body to behave in a certain way once puberty begins) and an activational role (triggering certain behavioral and physical changes). During puberty, the adolescent’s hormonal balance shifts strongly towards an adult state; the process is triggered by the pituitary gland, which secretes a surge of hormonal agents into the blood stream and initiates a chain reaction.

Puberty occurs over two distinct phases, and the first phase, adrenarche, begins at 6 to 8 years of age and involves increased production of adrenal androgens that contribute to a number of pubertal changes—such as skeletal growth. The second phase of puberty, gonadarche, begins several years later and involves increased production of hormones governing physical and sexual maturation.

Sexual Maturation

During puberty, primary and secondary sex characteristics develop and mature. Primary sex characteristics are organs specifically needed for reproduction—the uterus and ovaries in females and testes in males. Secondary sex characteristics are physical signs of sexual maturation that do not directly involve sex organs, such as development of breasts and hips in girls, and development of facial hair and a deepened voice in boys. Both sexes experience development of pubic and underarm hair, as well as increased development of sweat glands.

The male and female gonads are activated by the surge of the hormones discussed earlier, which puts them into a state of rapid growth and development. The testes primarily release testosterone and the ovaries release estrogen; the production of these hormones increases gradually until sexual maturation is met.

For girls, observable changes begin with nipple growth and pubic hair. Then the body increases in height while fat forms particularly on the breasts and hips. The first menstrual period (menarche) is followed by more growth, which is usually completed by four years after the first menstrual period began. Girls experience menarche usually around 12–13 years old. For boys, the usual sequence is growth of the testes, initial pubic-hair growth, growth of the penis, first ejaculation of seminal fluid (spermarche), appearance of facial hair, a peak growth spurt, deepening of the voice, and final pubic-hair growth. (Herman-Giddens et al, 2012).^[3] Boys experience spermarche, the first ejaculation, around 13–14 years old.

Reactions Toward Puberty and Physical Development

The accelerated growth in different body parts happens at different times, but for all adolescents it has a fairly regular sequence. The first places to grow are the extremities (head, hands, and feet), followed by the arms and legs, and later the torso and shoulders. This non-uniform growth is one reason why an adolescent body may seem out of proportion. Additionally, because rates of physical development vary widely among teenagers, puberty can be a source of pride or embarrassment.

Most adolescents want nothing more than to fit in and not be distinguished from their peers in any way, shape or form (Mendle, 2015).^[4] So when a child develops earlier or later than his or her peers, there can be long-lasting effects on mental health. Simply put, beginning puberty earlier than peers presents great challenges, particularly for girls. The picture for early-developing boys isn’t as clear, but evidence suggests that they, too, eventually might suffer ill effects from maturing ahead of their peers. The biggest challenges for boys, however, seem to be more related to late development.

As mentioned in the Khan Academy video about physical development, early maturing boys tend to be stronger, taller, and more athletic than their later maturing peers. They are usually more popular, confident, and independent, but they are also at a greater risk for substance abuse and early sexual activity (Flannery, Rowe, & Gulley, 1993; Kaltiala-Heino, Rimpela, Rissanen, & Rantanen, 2001). Additionally, more recent research found that while early-maturing boys initially had lower levels of depression than later-maturing boys, over time they showed signs of increased anxiety, negative self-image and interpersonal stress. (Rudolph, Troop-Gordon, Lambert, & Natsuaki, 2014).^[5]

Early maturing girls may be teased or overtly admired, which can cause them to feel self-conscious about their developing bodies. These girls are at increased risk of a range of psychosocial problems including depression, substance use and early sexual behavior (Graber, 2013).^[6] These girls are also at a higher risk for eating disorders, which we will discuss in more detail later in this module (Ge, Conger, & Elder, 2001; Graber, Lewinsohn, Seeley, & Brooks-Gunn, 1997; Striegel-Moore & Cachelin, 1999).

Late blooming boys and girls (i.e., they develop more slowly than their peers) may feel self-conscious about their lack of physical development. Negative feelings are particularly a problem for late maturing boys, who are at a higher risk for depression and conflict with parents (Graber et al., 1997) and more likely to be bullied (Pollack & Shuster, 2000).

School During Adolescence

Secondary Education

Adolescents spend more waking time in school than in any other context (Eccles & Roeser, 2011). Secondary education is traditionally grades 7-12 and denotes the school years after elementary school (known as primary education) and before college or university (known as tertiary education). Adolescents who complete primary education (learning to read and write) and continue on through secondary and tertiary education tend to also have better health, wealth, and family life (Rieff, 1998).^[7] Because the average age of puberty has declined over the years, middle schools were created for grades 5 or 6 through 8 as a way to distinguish between early adolescence and late adolescence, especially because these adolescents different biologically, cognitively and emotionally and definitely have different needs.

Transition to middle school is stressful and the transition is often complex. When students transition from elementary to middle school, many students are undergoing physical, intellectual, social, emotional, and moral changes (Parker, 2013). ^[8] Research suggests that early adolescence is an especially sensitive developmental period (McGill et al., 2012).^[9] Some students mature faster than others. Students who are developmentally behind typically experience more stress than their counterparts (U.S. Department of Education, 2008).^[10] Consequently, they may earn lower grades and display decreased academic motivation, which may increase the rate of dropping out of school (U.S. Department of Education, 2008). For many middle school students, academic achievement slows down and behavioral problems can increase.

Specific Middle School Issues

Regardless of a student’s gender or ethnicity, middle school is challenging. Although young adolescents seem to desire independence, they also need protection, security, and structure (Brighton, 2007).^[11] Baly, Cornell, & Lovegrove (2014) found that bullying increases in middle school, particularly in the first year.^[12] Additionally, unlike elementary school, concerns arise regarding procedural changes. Just when egocentrism is at it’s height, students are worried about being thrown into an environment of independence and responsibility. They are expected to get to and from classes on their own, manage time wisely, organize and keep up with materials for multiple classes, be responsible for all classwork and homework from multiple teachers, and at the same time develop and maintain a social life (Meece & Eccles, 2010).^[13] Students are trying to build new friendships and maintain ones they already have. As noted throughout this module, peer acceptance is particularly important.

Another aspect to consider is technology. Typically, adolescents get their first cell phone at about age 11 and, simultaneously, they are also expected to research items on the Internet. Social media use and texting increase dramatically and the research finds both harm and benefits to this use (Coyne et al., 2018).^[14]

High School

As adolescents enter into high school, their continued cognitive development allows them to think abstractly, analytically, hypothetically, and logically, which is all formal operational thought. High school emphasizes formal thinking in attempt to prepare graduates for college where analysis is required. Overall, high school graduation rates in the United States have increased steadily over the past decade, reaching 83.2 percent in 2016 after four years in high school (Gewertz, 2017).^[15] Additionally, many students in the United States do attend college. Unfortunately, though, about half of those who go to college leave without a degree (Kena et al., 2016).^[16] Those that do earn a degree, however, do make more money and have an easier time finding employment. The key here is understanding adolescent development and supporting teens in making decisions about college or alternatives to college after high school.

Anxiety and Depression

Developmental models of anxiety and depression also treat adolescence as an important period, especially in terms of the emergence of gender differences in prevalence rates that persist through adulthood (Rudolph, 2009) ^[17] Starting in early adolescence, compared with males, females have rates of anxiety that are about twice as high and rates of depression that are 1.5 to 3 times as high (American Psychiatric Association, 2013) ^[18] Although the rates vary across specific anxiety and depression diagnoses, rates for some disorders are markedly higher in adolescence than in childhood or adulthood. For example, prevalence rates for specific phobias are about 5% in children and 3%–5% in adults but 16% in adolescents. Additionally, some adolescents sink into major depression, a deep sadness and hopelessness that disrupts all normal, regular activities. Causes include many factors such as genetics and early childhood experiences that predate adolescence, but puberty may push vulnerable children, especially girls into despair.

During puberty, the rate of major depression more than doubles to an estimated 15%, affecting about one in five girls and one in ten boys. The gender difference occurs for many reasons, biological and cultural (Uddin et al., 2010) ^[19] Anxiety and depression are particularly concerning because suicide is one of the leading causes of death during adolescence. Some adolescents experience suicidal ideation (distressing thoughts about killing oneself) which become most common at about age 15 (Berger, 2019) ^[20] and can lead to parasuicide, also called attempted suicide or failed suicide. Suicidal ideation and parasuicide should be taken seriously and serve as a warning that emotions may be overwhelming.

Developmental models focus on interpersonal contexts in both childhood and adolescence that foster depression and anxiety (e.g., Rudolph, 2009) ^[21] Family adversity, such as abuse and parental psychopathology, during childhood sets the stage for social and behavioral problems during adolescence. Adolescents with such problems generate stress in their relationships (e.g., by resolving conflict poorly and excessively seeking reassurance) and select into more maladaptive social contexts (e.g., “misery loves company” scenarios in which depressed youths select other depressed youths as friends and then frequently co-ruminate as they discuss their problems, exacerbating negative affect and stress). These processes are intensified for girls compared with boys because girls have more relationship-oriented goals related to intimacy and social approval, leaving them more vulnerable to disruption in these relationships. Anxiety and depression then exacerbate problems in social relationships, which in turn contribute to the stability of anxiety and depression over time.

Identity Formation: Who am I?

Adolescents continue to refine their sense of self as they relate to others. Erik Erikson referred to life’s fifth psychosocial task as one of identity versus role confusion when adolescents must work through the complexities of finding one’s own identity. Individuals are influenced by how they resolved all of the previous childhood psychosocial crises and this adolescent stage is a bridge between the past and the future, between childhood and adulthood. Thus, in Erikson’s view, an adolescent’s main questions are “Who am I?” and “Who do I want to be?” Identity formation was highlighted as the primary indicator of successful development during adolescence (in contrast to role confusion, which would be an indicator of not successfully meeting the task of adolescence). This crisis is resolved positively with identity achievement and the gain of fidelity (ability to be faithful) as a new virtue, when adolescents have reconsidered the goals and values of their parents and culture. Some adolescents adopt the values and roles that their parents expect for them. Other teens develop identities that are in opposition to their parents but align with a peer group. This is common as peer relationships become a central focus in adolescents’ lives.

Expanding on Erikson’s theory, Marcia (1966)^[22]) described identify formation during adolescence as involving both decision points and commitments with respect to ideologies (e.g., religion, politics) and occupations. Foreclosure occurs when an individual commits to an identity without exploring options. Identity confusion/diffusion occurs when adolescents neither explore nor commit to any identities. Moratorium is a state in which adolescents are actively exploring options but have not yet made commitments. As mentioned earlier, individuals who have explored different options, discovered their purpose, and have made identity commitments are in a state of identity achievement.

Developmental psychologists have researched several different areas of identity development and some of the main areas include:

• Religious identity: The religious views of teens are often similar to those of their families (Kim-Spoon, Longo, & McCullough, 2012) ^[23] Most teens may question specific customs, practices, or ideas in the faith of their parents, but few completely reject the religion of their families.
• Political identity: An adolescent’s political identity is also influenced by their parents’ political beliefs. A new trend in the 21st century is a decrease in party affiliation among adults. Many adults do not align themselves with either the democratic or republican party and their teenage children reflect their parents’ lack of party affiliation. Although adolescents do tend to be more liberal than their elders, especially on social issues (Taylor, 2014) ^[24], like other aspects of identity formation, adolescents’ interest in politics is predicted by their parents’ involvement and by current events (Stattin et al., 2017). ^[25]
• Vocational identity: While adolescents in earlier generations envisioned themselves as working in a particular job, and often worked as an apprentice or part-time in such occupations as teenagers, this is rarely the case today. Vocational identity takes longer to develop, as most of today’s occupations require specific skills and knowledge that will require additional education or are acquired on the job itself. In addition, many of the jobs held by teens are not in occupations that most teens will seek as adults.
  

  

• Ethnic identity: Ethnic identity refers to how people come to terms with who they are based on their ethnic or racial ancestry. According to the U.S. Census (2012) more than 40% of Americans under the age of 18 are from ethnic minorities. For many ethnic minority teens, discovering one’s ethnic identity is an important part of identity formation. Phinney (1989)^[26] proposed a model of ethnic identity development that included stages of unexplored ethnic identity, ethnic identity search, and achieved ethnic identity.
• Gender identity: A person’s sex, as determined by his or her biology, does not always correspond with his or her gender. Sex refers to the biological differences between males and females, such as the genitalia and genetic differences. Gender refers to the socially constructed characteristics of women and men, such as norms, roles, and relationships between groups of women and men. Many adolescents use their analytic, hypothetical thinking to question traditional gender roles and expression. If their genetically assigned sex does not line up with their gender identity, they may refer to themselves as transgender, non-binary, or gender-nonconforming.
  • Gender identity refers to a person’s self-perception as male, female, both, genderqueer, or neither. Cisgender is an umbrella term used to describe people whose sense of personal identity and gender corresponds with their birth sex, while transgender is a term used to describe people whose sense of personal identity does not correspond with their birth sex. Gender expression, or how one demonstrates gender (based on traditional gender role norms related to clothing, behavior, and interactions) can be feminine, masculine, androgynous, or somewhere along a spectrum.
  • Fluidity and uncertainty regarding sex and gender are especially common during early adolescence, when hormones increase and fluctuate creating difficulty of self-acceptance and identity achievement (Reisner et al., 2016).^[27] Gender identity, like vocational identity, is becoming an increasingly prolonged task as attitudes and norms regarding gender keep changing. The roles appropriate for males and females are evolving and some adolescents may foreclose on a gender identity as a way of dealing with this uncertainty by adopting more stereotypic male or female roles (Sinclair & Carlsson, 2013) ^[28]. Those that identify as transgender or other face even bigger challenges.