From day one when we were born, parts of our body have been growing – some slowly, some super fast. We all walked and talked at different times to our friends of the same age - and our teeth grew (and fell out!) at different times. Puberty is the same.

You may notice some changes in yourself, or others in your class, from age 8 in girls and 9 in boys all the way up to 13 (girls) or 14 (boys). Most girls will start puberty between age 11 and 12 and it's totally normal for boys to go through puberty later than girls.

So what causes these changes? It is chemicals called hormones that circulate in our bloodstream. Hormones and their effect on puberty will be covered in other fact sheets.

In girls, the first sign of puberty is breast and pubic hair development, followed within about a year by a fast growth spurt.

For boys, the fast growth spurt happens relatively later, after genital and pubic hair development. In boys, the penis will also grow bigger; boys will have erections and may experience ejaculation. Some boys may struggle to control ‘cracks’ and ‘squeaks’ as their voice deepens.  Body hair will start to appear on the face and chest.,

In both girls and boys, oil and sweat glands in the skin will be more active and we may notice body odour, which means we may have to wash more frequently and use a deodorant. The increased oiliness on our face can lead to pimples.

We will also experience emotional and intellectual changes besides the physical ones. Such as changes to the way we think, and some things may become more important us as we mature. Mood swings from happy to sad are completely normal.

Relax – everyone encounters these changes on their way to adulthood. The adults we know had the same hang-ups too – although sometimes we think they’ve forgotten how difficult and confusing growing up can be. Give them a break, they’re getting old – their memory doesn’t work as well as ours!