The National Consumer Council Education Forum, which raised the objection, is opposing Government proposals legally to regulate pupils' conduct.
Under plans unveiled in last month's White Paper on the Citizen's Charter, a formal agreement - signed by parents and heads during the admission process - would govern pupils' dress, punctuality and standards of homework. But the NCC said there was a danger the arrangement could be one-sided. Forum chairman Maurice Plaskow said: "Any agreement needs to be two-way. For example, a parent undertaking to monitor their child's homework must be matched by the school's commitment to set and mark it regularly."Reuse content