In England and Wales compulsory school begins at the age of five, but before that age children can go to a nursery school. School is compulsory till the children are 16 years old. The school year is divided into three terms with the intervals between them during Christmas and Easter holidays lasting about two weeks each and summer holiday which is usually six weeks long. All kinds of out-of-class activities are part of school life in Britain. Schoolchildren attend a primary school for 6 years (5 to 11 years). In Primary School and First School children learn to read and write and the basis of arithmetic. In the higher classes of Primary School (or in Middle School) children learn geography, history, religion and, in some schools, a foreign language. Then children go to the Secondary School. When students are 16 years old they may take an exam in various subjects in order to have a qualification. These qualifications can be either G.C.S.E. (General Certificate of Secondary Education) or "O level" (Ordinary level). Weak students may only sit for three or four subjects. Better students take ten subjects. At the age of 16 about two thirds of these pupils leave school and get jobs. About one-third stay on at school until the age of 18, preparing themselves for higher education. They have to take further examinations which are necessary for getting into university or college. Some parents choose private schools for their children. They are very expensive but considered to provide a better education and good job opportunities. In England there are 47 universities, about 400 colleges and institutes of higher education. The oldest universities in England are Oxford and Cambridge. Generally, universities award two kinds of degrees: the Bachelor's degree and the Master's degree.