School - complaints procedure
Complaints about schools should be made directly to the school concerned.
This is because complaints about schools have to be dealt with by the school rather than by the Local Education Authority. Every school is required to have a Complaints Policy which is available on request.
However, in the first instance you should discuss the matter with the form teacher, or the head of year at the school and, subsequently, if you wish to complain formally you should write to the headteacher.