Kenny Frederick, a headteacher and member of the NAHT executive, has accused the Education Secretary Michael Gove of wanting to "bring us back to 1950s".
Speaking on the BBC's Radio 5 Live, she said that Mr Gove has not listened to teachers and that his plan was destined to "fall flat on its face".
Mr Gove is expected to receive an angry reception when he speaks at the NAHT conference in Birmingham this afternoon.
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Former Chancellor Lord Geoffrey Howe was Margaret Thatcher's longest-serving Cabinet minister, also taking on the role of Foreign Secretary.
Lord Geoffrey Howe is known by many for his resignation speech which was seen as the catalyst which destroyed Margaret Thatcher.