Sexuality Resource Center for Parents: Tools, Tips, and Tricks for Teaching Children about Human Sexuality

Sexual Development from 018 Years Old

A lot of things need to happen in the sexual development of children in order for them to be sexually healthy adults. In order for you to understand the tasks they need to accomplish, let’s take a look at sexual development from birth through 18 years old of a typical child. We're not just going to give you the facts on sexual development – we're also going to tell you the messages that we think children should be receiving as they go through the different stages of sexual development. If you disagree with any of these messages, that's okay. We don’t have to agree on everything, but we do think certain messages need to be given.

The facts appear in regular type and the messages appear in bold type.

Sexual Development from 0 – 18 Months Old

Does a 3-month old baby understand it when you say, “I love you, I love you”? Sorry, but the answer is "no." But they do understand what it means to be loved. How? Through nurturing touch. Between birth and 18 months, children begin to develop negative or positive attitudes toward their own bodies based on the kind of touch that they receive. Through nurturing body touch, they learn to value themselves and they learn what it means to be loved.

Amazingly enough, between birth and 18 months, children begin to develop their identity as either female or male. If a child perceives one gender as better or worse than the other, the child will begin to apply those values to themselves. Children learn early because messages are sent early, beginning in-utero (research has shown that how people react to the kick of a fetus depends on whether they think the fetus is a girl or a boy) and continuing from the moment a child is born.

Between birth and 18 months, children begin to differentiate between female and male roles.

Between birth and 18 months, children discover their genitals and begin to touch themselves for pleasure. Children this age are not masturbating to orgasm.

A child's feelings about their own body are influenced by how adults respond to masturbation. Many people believe that masturbation is harmful, but research now tells us that masturbation is a healthy thing for children and adults to do. It feels good and some children find comfort in holding onto their genitals in stressful situations.

Current research indicates that a person’s sexual orientation is established by the time they are born. Sexual orientation is not a choice, it is not influenced by the way a child is raised, and there is nothing a parent can do to change their child’s sexual orientation.

Sexual Development from 18 Months – 3 Years Old

Between the ages of 18 months and 3 years, children learn the language for body parts and functions. Children often attach a sense of naughtiness to using this language, instead of viewing it as everyday, acceptable vocabulary. Why? Because parents unintentionally attach this sense of naughtiness.

Let us demonstrate the typical way a parent teaches their young child about body parts...

“Touch your toes. Good. Touch your feet. Good. Touch your legs. Good. Touch your belly. Good. Touch your arms. Good. Touch your shoulders. Good. Touch your neck. Good. Touch your head. Good.”

What did the parent leave out? You guessed it – the genitals. And what message does this give? Genitals are not really part of the body; they are unmentionable; there’s something wrong with them.

Okay, then we make it worse. We say to children in a nice, adult voice, “This is your knee. This is your elbow.” Then, for some reason, our voice jumps a couple of octaves and gets silly-sounding. “This is your wee-wee.” Do we have silly names for knees and elbows? No. What message does this give? Same as above: Genitals are not really part of the body; they are unmentionable; there’s something wrong with them.

We don’t do this on purpose, but it does affect children.

We need to identify all body parts using the correct language so we don’t convey the impression that there is something wrong with them. Our goal should be to normalize the discussion of sexuality with children, but it’s hard to normalize something that’s “wrong.”

There are three additional reasons for the correct naming of body parts. First of all, research has shown that when a child knows the correct words for private body parts, they are more likely to report sexual abuse, if it occurs, than when the child doesn’t know the correct words. Second, using correct words is important when abuse is being investigated. A child who uses the correct words when talking to police, lawyers, or judges is more likely to be understood and believed. And finally, in cases of sexual abuse, if you can't name what happened, you can't create distance from the event. Language creates distance, and distance helps a person recover from the abuse.

Even if you use the correct words, you may still hear your child use the wrong words. Let’s face it, children hear all sorts of silly words from other children. But the next time your child comes home and says their wee-wee hurts, take the time to say, “In our family, we don’t use the word wee-wee; we use the word penis.” And in case you’re wondering… no, you haven’t ruined your child for life if you’ve been using the silly words up until now. You can fix this. No problem. Just start using the correct words.

As a child's body is all-important to them, so are the things that come out of it. If a two or three-year-old gains the impression during toilet training that these things are dirty and disgusting, they may believe the places they came out of are just as dirty and disgusting.

Toilet training should be handled calmly and matter-of-factly. The right words won't count for much if your body language shows disgust or discomfort.

Children this age become certain of their own gender, but not sure of its permanence – they know they are a boy or a girl, but they don’t think of this as a permanent condition! Questions about why some children have penises and some don't are likely to come up at this time, especially if a child has the chance to see others naked.

Three-year-olds are interested in the different positions for urinating. Girls attempt to urinate standing up.

Many young girls think that boys have something (a penis) and they have nothing. Be sure young girls understand that they have a special part called the vulva. Tell them it’s just harder to see than the penis. You can even use a small mirror to show a young girl the parts of her vulva.

Between 18 months and three years, children begin to behave and perceive others in gender-typed ways.

If we want children to consider all genders equal, then our words and actions must support that belief.

By the age of three, children should understand that their bodies belong to themselves and that they have a right to say “no” to unwanted touch.

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Sexual Development from 3 – 5 Years Old

Please Remember...

The facts on sexual development appear in regular type.

The messages we think children should be receiving appear in
bold type.


Between the ages of three and five, children demonstrate a growing awareness of the body and its functions. They are talkative and curious about everything, including their bodies and the bodies of others. They want to snuggle in bed with parents, join them in the bathroom, watch them getting dressed, or handle their genitals.

Just because these behaviors are normal doesn’t mean you have to allow them. Children learn about privacy and modesty based on the standards established by their families.

The big question, “Where did I come from?” is usually first asked around the age of three or four.

If a child has the courage to ask this question, you should have the courage to answer it honestly. Again, you haven’t ruined your child for life if you’ve told them they were found on the doorstep or delivered by a stork. Just apologize for your lie and tell them the truth now. If you have a child with typical development or a child with a physical disability, click here to learn how to answer their questions about sex and sexuality. If you have a child with a developmental disability, click here to learn how to answer their questions about sex and sexuality.

Expect questions about babies, pregnancy, and breast-feeding too.

Again, answer these questions honestly and simply.

Young children are so literal-minded that the analogies often used to explain birth can be misleading, confusing, or even frightening to them. Many children have thought that there was a plant growing inside a pregnant woman just because they were told that the man supplied “a seed” (instead of “sperm”). And be very clear about the difference between a chicken egg and a human egg!

Children have no notion of adult sexuality, so there is no need to go into the physical and emotional aspects of having sex.

“Sex play” begins around the age of three or four and will continue up until puberty.

“Sex play” for three to five-year-olds includes playing “doctor,” exploring sexuality through play with dolls, and mimicking adult behavior. It is common to see children peeking under one another's clothing, undressing their dolls, and checking out the “bottoms” of pets and stuffed animals.

“Sex play” is completely normal. It is another way for children to find out about their own bodies and the bodies of others. It is curiosity-based with no erotic or sexualized meanings. It is adults who add these interpretations – causing them to flip out when they see “sex play.” And overreacting to this normal behavior can send some very strong negative messages about sexuality.  

Just because it is normal for your child to engage in “sex play” doesn’t mean you always have to allow it. Here’s an example: You walk into the bathroom and find your four year-old daughter and your four year-old neighbor’s son naked and looking at each other’s genitals. It’s typical behavior and it would probably not require interference on your part except that you don’t think your neighbor would approve. If that’s the case, say to the children, “Oh, I see you are both interested in looking at each other’s bodies. It’s good to be curious, but let’s pull up our pants and find something else to do.” It’s probably a good idea to notify the neighbor about what happened. They may hear about it from their son anyway, so it’s better that they don’t think you were trying to hide something. Later, remind your daughter about the incident and tell her again that it’s good to be curious, but that she should come to you with her questions. You can then use this opportunity to read a book with her about bodies.

Children this age establish a firm internal belief that they are either female or male, and they work hard on developing their sexual identities as girls or boys. They imitate the same-sex parent and want to include all they know about gender roles in their play. “You be the mommy and I'll be the daddy” is frequently heard in play. The mommy and daddy games usually involve who goes to work, who shops, who cooks, who drives the car, and so on. The games do not involve sexual exploration. This is the age when little girls want to grow up and marry their dads, and little boys want to grow up and marry their moms. This is a sign of the extent to which they identify with and are imitating their same-sex parent.

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Sexual Development from 5 – 6 Years Old

This is a period of richly imaginative activity, during which some of the most bizarre misconceptions can be formed concerning physical facts. It is for this reason that simple and accurate information about the body and its functions should be presented.

Children continue to work hard on developing their sexual identities and roles as girls or boys. They still imitate the same-sex parent and want to include all they know about gender roles in their play. These roles are often stereotyped even when the parents try their hardest not to stereotype females and males – an indication of just how strong other influences (such as other family members, friends, or television) can be.

Children this age want to know that their family is okay.

They should understand that there are many different types of family situations, and that no single type is better than the rest.

Masturbation (touching one’s own genitals for pleasure) is quite common at this age. Children this age are not masturbating to orgasm.

Again, masturbation is a healthy thing for children to do – it feels good and it's a comfort for some children. If children are allowed to masturbate in the absence of negative messages, it increases the likelihood that they will become sexually healthier and happier adults. After all, if you know what gives you pleasure, you can tell your partner what gives you pleasure.

By this age, children should know that masturbation should only be done in private.

If you still believe that masturbation is harmful, then let your child know that masturbation is not acceptable in your family. Try to do so without making your child feel guilty about their behavior. It is, after all, a normal behavior. And understand that your child will probably masturbate anyway.

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Sexual Development from 6 – 9 Years Old

Please Remember...

The facts on sexual development appear in regular type.

The messages we think children should be receiving appear in
bold type.


During this period, children become much more intellectually developed and, for the first time, are able to grasp all of the basic facts about sex, conception, pregnancy, and the birth process.

They still do not understand the emotional and erotic feelings that are part of sexuality. They may understand sex and conception very well, but may assume that their parents have only had sex once or twice, for the purpose of producing children.

Children in this age group first begin to be preoccupied with being “normal” and consequently are interested in all non-normal things, such as twins, Siamese twins, or people with disabilities.

They continue to develop their conception of what it means to be a girl or a boy, and they start to develop a more complex sense of the differences in gender roles.

Children should be exposed to non-stereotyped gender roles.

Children begin to conform to peer group style of dress and speech. At this age, boys experience more pressure than girls to adhere to gender-role expectations in areas such as choice of toys, hobbies, clothing, and hair styles.

“Sex play” continues.

Masturbation is quite common at this age. As with younger children, children this age are not masturbating to orgasm – they are just touching their genitals for pleasure or comfort.

Children this age may whisper, say out loud, or write sexual words. There is also an interest in sexual jokes. Children know that adults find this kind of behavior unacceptable, so they won’t do it in your presence. If you ever happen upon a group of giggling 6-9 year olds, and the giggling suddenly stops, it's a pretty safe bet that the giggling had something to do with sex.

At eight years of age, some girls are already starting to go through puberty.

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Sexual Development from 9 – 14 years old

The experts don’t all agree but we can safely say that, on average, puberty begins for girls between the ages of 8 and 13 and for boys between the ages of 10 and 15. It usually takes about 3-4 years to get through puberty.

Puberty has its unpleasant moments, but it would be a lot less unpleasant if everyone went through it at the same time and rate. One of the most difficult aspects for pre-teens and teens to handle is the wide variation in the rate of physical development at a given age. And so the question “Am I normal?” becomes almost an obsession now. Or to word it differently, the question “What’s wrong with me?” becomes almost an obsession now. And no wonder. If you’re the first girl in your class to develop breasts, that’s a bad thing. If you’re the last girl in your class to develop breasts, that’s a bad thing. If you’re a boy who gets an erection in front of the class, that’s a bad thing. If you’re a boy whose voice cracks when you’re trying to impress a girl, that’s a bad thing. Getting your period when you’re not prepared – bad. If you’re a boy, and all the girls are taller than you – bad. Uncontrollable mood swings for both girls and boys – bad. The variations are almost endless. Throw in pimples and body odor and you can begin to understand why puberty can be such a tough time for pre-teens and teens.

Now you may know that we all get through puberty, but for these pre-teens and teens, anxiety over physical development may be accompanied by the fear that all will not turn out well. Consider the boy who develops little breasts. This happens to more than half of all boys during puberty – it’s normal and the breasts go away in a year to 18 months. But if nobody told you this, you might think you got the wrong hormones and you were turning into a girl.

Pre-teens and teens need to know that it is “normal” for everyone to be different, that everyone eventually gets through puberty, and that the anxiety and confusion caused by puberty are not permanent conditions. They need to know that they are not alone in their self-doubts and fears.

Boys worry about their penis size. Girls worry about their breast size.

Again, we must reassure our children that no two people are the same, and that it is normal to be different.

Many pre-teens and teens become dissatisfied with their weight or body shape.

Poor body image can inhibit healthy sexual relationships. Pre-teens and teens need to know that bodies come in all shapes and sizes; that each of us has a basic shape that can't be changed, no matter how much or how little we eat or exercise; and that we don't have to accept society's current notion of the “perfect” body.  

Lots of changes in friendships take place during these years, and rejection by old friends can be very painful. Children tend to choose friends who are going through puberty at the same time and rate as themselves. This often ends up being harder on the boys than the girls because boys generally begin puberty later than girls. Imagine the boy and girl who have been friends since they were three years old. The girl hits puberty, she takes off like a rocket, and she no longer wants anything to do with an old friend who’s still small and immature.  

We can’t make that girl still be friends with the boy, but we can ask her to be nice about ending the friendship.  

Those girls who mature more quickly may become interested in dating. In order to date someone at their own maturity level, they will probably have to date older boys.

Consequently, they will need to know the purposes and considerations of dating, and about the potential for exploitive relationships.

By the end of this stage, boys will also begin to show an interest in dating, but they often have a very strange way of showing that they like a girl. Do you know how they show it? That's right, by teasing or hitting her.

In striving for an individual identity and independence, boys and girls regard the opinions of their friends with increasing importance. Children this age have begun another separation process from their parents.

We need to let pre-teens and teens “fit in” with their peers. But we must encourage them to think for themselves and not get carried away by the crowd.

Masturbation is quite common at this age, and some young people are very much concerned about the feelings of guilt that frequently accompany this behavior.

Masturbation is a healthy thing to do – it feels good and, if done in the absence of negative messages, it increases the likelihood that young people will become sexually healthier and happier adults. After all, if you know what gives you pleasure, you can tell your partner what gives you pleasure.

Pre-teens and teens need to know that deciding whether or not to masturbate is a personal choice that may depend upon the values of their family. Even when families don’t object to masturbation, young people should understand that it's okay if you masturbate and okay if you don't.

Pre-teens and teens are fascinated with the way their bodies change. It is common for friends of the same gender to look at and touch each other's genitals. This is one of the ways they learn that they are normal. This kind of exploration has nothing to do with sexual orientation.

Children this age may ask a lot of questions about sexual orientation. At this point in their lives, they have probably heard a lot of misinformation about the topic.

Pre-teens and teens should understand that sexual orientation is not a choice, and that the only difference between heterosexuals, bisexuals, and homosexuals is the gender of the persons to whom they are attracted.

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Sexual Development from 14 – 18 years old

Please Remember...

The facts on sexual development appear in regular type.

The messages we think children should be receiving appear in
bold type.


Teens are essentially self-conscious and self-concerned. They are struggling to cope with a changing body image, to develop controls over emotional drives, and to find their place in the world.

Self-esteem is shaky, and regardless of the facts of their social situation, teens are rarely secure in their acceptance by peers and adults. Teens want to know that they are valued, and so they try to prove it. Unfortunately, the way they try to prove it is by getting a boyfriend or girlfriend. It’s hard to imagine a worse way of trying to prove yourself because rejection is always a distinct possibility.

Though some teens may withdraw socially to protect themselves from rejection, most will feel the need to be accepted, attached, and sought after.

Because teens have profound fears about being “different,” they are easy targets for peer pressure and bad advice.

Again, we need to let teens “fit in” with their peers. But they must also understand that they are responsible for the choices they make.

Relationships with parents may be especially intense and full of conflict. On one side of the conflict is a renewed demand for attention; on the other side is the continuing effort to withdraw from dependency. And it’s not like these two sides take turns from one week to the next. It may be more like from one moment to the next.

Teens need to know that, though we may find certain behaviors unacceptable, we still accept them for who they are.

Girls are interested in the roles of womanhood; boys try out the ways of men whom they respect.

Teens should understand the differences between biological sex roles and socially assigned gender roles. They need to know that there do not have to be prescribed gender roles for dating partners. Teens should understand that gender role stereotypes are harmful to both women and men.

Fourteen, fifteen, and sixteen year olds are also beginning to test out heterosexual closeness on a more mature level. This may include having sex. Early sexual experiences for teenage girls may be especially unenjoyable, and teens are often aware that they are not emotionally ready for the behaviors they are trying out. The question then arises as to why they would still choose to engage in these behaviors. They do so for various reasons: they think all of their peers are doing it; pressure from a boyfriend or girlfriend; to declare their freedom from childhood dependence and restrictions; curiosity; misinformation; and simply to take risks and test their limits.

Teens need to match their behaviors with their emotional readiness.

Seventeen and eighteen year olds are more capable of handling the emotional side of new sexual behaviors. Since these young people are now exposed to a wide range of behaviors, they are all the more involved in working out standards for themselves. In so doing, they may sharply challenge the very behaviors they wish to engage in.

Teenage girls often do not plan for their first sexual experience, because to do so would be to acknowledge the fact – even to themselves – that they are interested in sex.

Teenage boys often feel the pressure to have sex with a girl so that other boys won't think they are gay.

Teens must realize that there are consequences for any sexual activity that they engage in. They must know how to have relationships without getting hurt and without hurting others.

Sexual feelings can be cause for great concern. Sexual wishes or fantasies can be seen as being equivalent to the act.

Teens need to know we can’t control our feelings but we can control our behaviors. Teens need to recognize that sexual wishes or fantasies are normal, and that we do not have to act on these wishes or fantasies.

Finally, teens should understand the positive role that sexuality and sexual pleasure should play in one's life.


Compiled and adapted by Sexuality Resource Center for Parents.

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