Most schools separate their pupils into different houses for pastoral purposes. Usually houses represent all age groups and are competitive (sometimes described as vertical or parallel houses). They will have roughly equal numbers from each year group and may have a senior pupil as head of house; they may have distinguishing ties, sports colours, badges etc.
Where the vast majority of pupils board, these houses will often be the central element of the school structure; it is where pupils live, study and eat. In these cases, the house is pastoral, competitive and domestic and is likely to have a strong identity − in some cases, initial application is made to the specific house rather than the school. In co-ed schools, the boarding houses are sometimes mixed and sometimes single-sex (though it is not always clear how eg a single girls’ house fits into a competitive house system). Boys’ and girls’ houses may be twinned for competitive purposes and, in a few cases, houses in a boys’ school are twinned with those of a neighbouring girls’ school.
Other boarding schools divide pupils by age group – sometimes called horizontal houses. There is quite commonly a separate sixth form house, even in schools with a vertical house system. In a school with relatively few boarders, the house may simply be a single unit of accommodation.