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Qualified teacher status (QTS) is the accreditation that enables you to teach in state-maintained and special schools in England and Wales.
Who needs QTS?
Anyone who wants to teach in a state-maintained school in England or Wales needs to gain qualified teacher status (QTS). To achieve this award, you need to complete a period of initial teacher training (ITT), which will enable you to meet the professional standards for QTS; a formal set of skills and qualities required to be an effective teacher.
and
Unqualified Teachers (UQTs)
The legislation that prescribes the 4 year rule is The Education (Specified Work and Registration) (England) Regulations 2003. The relevant paragraph is section 5 of schedule 2.
The same regulations define ?specified work? and who is permitted to carry it out. The general rules that apply are:
? They carry out specified work in order to assist or support the work of a qualified teacher.
? They are subject to the direction of a qualified teacher.
? The Head teacher is satisfied they have necessary skills, expertise and experience required to carry out specified work.