Secondary school is the next step up from primary school. Secondary schools are often called high schools or middle school in United States. In Britain, secondary schools may be public schools, grammar schools or comprehensive schools.
In Australia, a person will generally begin secondary school when they are at the age of 12 and finish (or graduate) when they are either 16 or 18 years of age. This is dependent upon whether they finish with year levels (or grades) 11 and 12. In secondary school, a person will advance through the year levels (or grades) each year.
In the United Kingdom, a person starts secondary school at the age of 11 and generally finishes secondary at either 16 or 18 depending on whether the secondary school has a sixth form offering post 16 education.
In the United States school system, secondary school is usually divided into two separate schools. One is called middle school and consists grades 6, 7, and 8. And the other is called high school and has grades 9 through 12. A person generally starts middle school at age 11 or 12 and starts high school at age 14 or 15 and finishes at age 18.
Generally a student goes to the high school for four years. Depending on the laws in each individual state, a student can drop out of high school; the minimum age is 16. If the student does graduate, he/she can plan to continue his/her studies to college or a university, or just join the workforce.
In some schools in Australia years 11 and 12 are just a normal part of high school. Some other schools may only progress through to year 10; in this case students will then go to college (years 11 and 12).
At the end of secondary school, students will usually take a unified examination. For example, students finishing secondary school in England take the General Certificate of Secondary Education (GCSE).