Joining a new school is stressful, so it is easier (for children and parents) to join with other new pupils. All schools will have principal entry ages – for secondary schools, usually 11 or 13; age 12 in Scotland. Many schools will take pupils at other ‘natural’ points related to the curriculum (such as the start of the GCSE course); a number take pupils at other ages and some (particularly international schools) take pupils at any stage.
A common point to change schools is at age 16, into the sixth form after GCSEs. Pupils may be struggling to meet the requirements of their present school’s sixth form, be looking for a school where they are treated more like an adult, or perhaps just feel fed up and in need of a change. It can also be a good opportunity to look for more appropriate courses (the IB or vocational A-levels). But it is not a universal panacea for everyone: the existing school will know pupils’ strengths and weaknesses and can teach them accordingly; and the disruption caused by moving schools can cut badly into short, intense sixth-form courses.