At what age does puberty begin?
Boys enter puberty at an average age of 11 (one year later than girls) but may occur anytime between 9 to 14 years. The first sign of puberty in boys is enlargement of the testicles and a thinning and reddening of the scrotum (testicular area).

What other changes occur during a boy's puberty?
Puberty involves changes, affecting the skeletal, muscular, reproductive and nearly all other bodily systems including:

Voice change
Part of the puberty affects your voice. As the larynx (or voice box) enlarges and the muscles or vocal cords grow, the voice may "crack". This is a normal part of the growth process. Eventually the voice will change to a more permanent "adult male" deeper tone.

Wet Dreams
During you puberty time, you may wake up in the morning with damp pajamas and sheets. These "wet dreams," or nocturnal emissions, are caused by an ejaculation (releasing of semen) that occurs during your sleep. This does not necessarily mean that you were having a sexual dream. Wet dreams are normal for all boys in their puberty stage and are just part of your growing up. You have nothing to do with it or can not prevent it from happening until it ceases as spontaneously as it occurred.

Involuntary Erections
During puberty, boys get erections spontaneously, without touching their penis and without having sexual thoughts. These unexpected erections can be quite embarrassing, especially if they occur in public - at school, for example. These unexpected erections are normal and are a sign that your body is maturing. They happen to all boys during puberty, and with time they will become less freque

Breast Enlargemennt
Do you know that many boys experience swelling of the breasts during the early years of puberty? It is felt as a bump under one or both nipples. Your breasts may also feel tender or even painful. After a few months, or even longer, the swelling will disappear. These boys will not develop true breasts. This is called pubertal gynecomastia and is due to the hormonal changes that occur during puberty.

Skin
Your skin may get more oily and begin to sweat more. This is because the skin's oil and sweat glands are growing too. Wash every day to keep your skin clean and to use a deodorant or antiperspirant. Almost all teenagers get acne at one time or another (see acne).

Body Size
During puberty, significant growth occurs too usually peaking about two years after the beginning of puberty. Your arms, legs, hands, and feet may grow faster than the rest of the body. Until the rest of your body catches up, you may feel a little clumsier than usual. Although boys and girls are generally of similar height during middle childhood, that changes with the beginning of puberty. In junior high school, girls are often taller than boys, but with time, boys catch up and usually surpass girls in terms of height.

When does puberty begin in girls?
In girls puberty begins on average at age 10. However pubertal changes can develop as early as 8 years or as late as 13 years old. Puberty generally starts earlier for girls than it does for boys. This is why many girls are taller and may act more mature than boys for a few years until the boys catch up.

The following are some of the changes girls go through during puberty:
Breast development
This is the first sign of puberty in girls. Usually, breasts start to develop as small, tender bumps under one or both nipples that will get bigger over the next few years. It is not unusual for your one breast to be larger than the other in other words, one to develop before the other. Also, when you first notice the lump beneath one nipple, you may worry that this is abnormal or a sign of a serious medical problem. You should not, as this is a part of normal breast development. Sometimes young girls, in whom breasts start to develop relatively early, may feel embarrassed and self-conscious. Wear loose-fitting clothing that disguises your early breast development. A "training bra" may be used for that reason as well.

Body Size
During puberty, significant growth occurs too usually peaking about two years after the beginning of puberty. Your arms, legs, hands, and feet may grow faster than the rest of your body. Until the rest of your body catches up, you may feel a little clumsier than usual. Although boys and girls are generally of similar height during middle childhood, that changes with the beginning of puberty. In junior high school, girls are often taller than boys, but with time, boys catch up and usually surpass girls in terms of height.

Skin
Your skin may get more oily and begin to sweat more. This is because the skin's oil and sweat glands are growing too. Wash every day to keep your skin clean and to use a deodorant or antiperspirant. Almost all teenagers get acne at one time or another (see acne).

Menstruation
First menstruation (called menarche) usually begins anytime between 9 and 16 years of age, about two years after the onset of puberty. On average, the first menses (period) occurs just before 13 (see menstruation).

When do menstrual periods begin in girls?
Menstruation usually begins around age 11, but it may happen as early as age 8, or as late as age 16. The beginning of menstruation is called "Menarche". Menarche usually happens in "Stage 4" of puberty, but can happen late in Stage 3 as well. While there are no real "signs" of an impending first period, there are signs that may let you know when it is likely to happen.
Use the following guide to see where in puberty you are, and you'll get an idea of when your first period may happen (see 5-stage model of puberty for girls)

About menstruation
Menstruation is the discharge of blood and tissue from the lining of your uterus each month. Menstruations (or menstrual periods) are part of the "female reproductive cycle". A typical menstrual cycle lasts 28 to 30 days, but can vary from 22 to 35 days.

How do menstruations start?
Several months before the first period, fluid or discharge may be secreted by the vagina. This substance may be clear or white in color, and watery to thick in consistency. This is called physiologic leukorrhea and it is normal. The very first period is usually very mild; only a few drops of blood. In some girls, menstrual periods occur monthly (regularly) from the beginning. While in others, periods may not be regular; for example, some girls either miss a period or have two periods in one month. During the first year of menstruation this varied, or irregular pattern is usually normal as it takes a while for the body to establish a regular menstrual pattern (cycle)

Keeping track of periods
When menstruations begin it is a good idea to keep track of the cycles with a calendar. This will help you know when your next period will start.

What other symptoms accompany menstruation?
• Cramps in the lower abdomen (dysmenorrhea) are usually normal. If the pain differs or is more severe than usual, medical attention should be sought.
Other symptoms include:
• Bloating
• Tender breasts
• Headache
• Feeling tired
• Mood swings
• Food cravings

What can help relieve menstrual cramps?
• Pain medications such as ibuprofen or acetaminophen as needed
• Exercise
• Relaxing/meditating
• Avoidance of sweets, salt and caffeine

Menstruation: When to worry
Medical attention should be sought if:
• Periods are heavier than usual or
• Last longer than a week,
• Menstruation differs from the usual pattern, or
• A period is skipped (once a regular pattern has been established)

Acne Vulgaris, one the most common skin problems in adolescents, which occurs more frequently in boys than in girls. Although most people experience acne between the ages of 9-17 years, it can either persist until or occur during adulthood as well. Severe acne may lead to permanent scarring and can be a source of significant psychological effects including anxiety, embarrassment and shame, especially during adolescence.

What causes acne?
Acne is a problem of the sebaceous glands, which are found in the skin. Ordinarily these glands produce "sebum" an oily substance that lubricates and protects the skin. Just before puberty, many hormones are made in the body, some of which actually stimulate the sebaceous glands to produce more sebum. This blocks the glands' openings or ducts and gives rise to a closed comedo (whitehead).

As the gland expands, it becomes an open comedo filled with darker material (blackhead). If bacteria (normally found on the skin), gets into the pimple, it will cause an infection creating pus and redness. In severe cases the pimple becomes quite big and is called nodulocystic. Depending on the progression, acne can range from mild, with small whiteheads without scarring, to the nodulocystic type with severe scarring.

Is acne hereditary?
It is thought that the tendency to develop acne is hereditary although the exact genetic pattern is not well understood.

Does diet or stress make acne worse?
Many myths exist about diet and acne. These have been dispelled by studies that have shown that foods such as chocolate, cola drinks, milk, ice cream, fatty foods and shellfish do not cause nor worsen acne. However, although it is not clear why, emotional stress especially in girls, may make acne worse.

On what part of the body does acne occur?
Since it is a problem of the sebaceous glands, acne affects areas of the body with the highest number of these glands including the face, neck, chest, and upper back.

What can make acne worse?
Repetitive pressure or rubbing of the skin by articles such as turtlenecks, bra straps, shoulder pads and helmets may worsen acne. Tight clothing, rubbing or picking the skin may also make acne worse.

How is acne treated?
The type and specific form (lotion, gel, cream or oral) of the treatment depends on the severity of the acne: This can range from simple topical treatment such as Retinoids, to Benzoyl Peroxide and antibiotics, and to oral Isoretinoin in severe cases. Generally, the more severe cases are treated by a dermatologist. What is important however, is that Acne Vulgaris, regardless of its severity, not be taken lightly if it becomes a source of emotional stress in teenagers.

Here are some practical tips for you to get your skin rid of acne:

Do
• Do wash your face gently twice daily with a mild soap cleanser
• Do also wash after activities such as sports or exercise that make you sweat
• Do use hair products, skin care products, and make-up that have 'oil-free' on the label
• Do eat a healthy diet rich in fish, fruits, and vegetables. This can help make your skin less oily

Don't
• Don't scrub your face with a washcloth
• Don't squeeze or 'pop' the pimples, because this can leave scars
• Don't wear tight clothes that rub against your skin, or use sporting equipment such as shoulder pads, helmets, and chin straps

There are lots of good things about joining in with a group, but what do you do when you don't want to do what all of your friends are urging you to do?

Most teens appreciate the right kind of peer pressure. "It's nice when people encourage others to try new things and support them," they say. A friend might motivate you to learn to play drums, try out for the basketball team, or ask out that girl you've been crushing on who seems to like you back.

But a friend might also pressure you to break your parents' rules, be mean to somebody, have sex when you're not ready to, or do drugs.

You love hanging with your buds. But what if you don't want to do what everyone else is doing?

How to Deal
Since there's a good chance you're going to run into that "Come on! We're all doing this!" biz, why not think now about what to do if you want to say no? Mentally rehearsing different scenarios and your responses helps prevent the "I got caught up in the moment" regrets.

First, there's the direct route. Picture yourself as a confident leader who has a say in what you do. Decide how you feel about things like putting down others, sex, alcohol, stealing, and drugs. A firm "I don't do that; count me out," is convincing if it's heartfelt. Realize that others may be looking for someone to take the lead in refusing to follow along. You could be that someone.

But it can be hard to stand up to a group of people. If you don't feel comfortable being direct, try these tips:
• Say you've got something else you must do: "I can't. I've got a test tomorrow. Gotta study."
• Let people know that you're on an honor code — that you're promised your parents you won't do things like drink or steal, and you're sticking to that promise.
• Find someone else who wants to say no. It's easier to stand up to a group when you've got company.
• Think of how you'll feel afterward if you do something you don't want to do. Regret is not fun to live with.
• Talk with someone you trust about how to deal with these situations. Chances are your older siblings or parents dealt with similar problems when they were your age, and they might have some helpful insight on how to deal.
• Be matter-of-fact when you decide to say "no" to your friends. Don't be angry or judgmental.

Why Is It So Hard?
Your friends influence you. It's wonderful to belong to a group, and to feel they like you. Plus, it can be a lot of fun to enjoy a group activity. Who wants to be known as a spoilsport?

Some qualities make it harder to be that one person who stands up to the group:
• Lack of confidence hinders your ability to assert yourself.
• If nothing else is happening in your life besides your friends, it makes their opinions seem all-important.
• Feeling unsure about your friendships may make you too eager to please.

The Payoff
So why stand your ground when it can be so difficult? Believe it or not, saying "no" to something you don't want to do may actually improve your social standing. According to Carol Weston, author of Girltalk and For Teens Only, "While a few people may think less of you, many others will quietly respect you more. Why? Because they may be impressed that you are your own person, and not just one of a crowd."

What's more, doing your own thing can make you feel good about yourself. "It can be empowering to resist peer pressure. Saying "no" to others can mean saying "yes" to yourself," says Weston. "When you stand up for yourself... it's like you're voting for yourself and being true to your own beliefs, and that always feels good.”

Sources used:
http://en.wikipedia.org/
http://www.teenwire.com/
Http://www.puberty101.com/