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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Guillier conceded a "severe defeat" defeat to his supporters as the result came in.
The outage struck Hartfield-Jackson Atlanta International Airport at around 1pm local time, stopping all outgoing flights.
It will be a chilly day for many parts with the highest temperatures, about 10 Celsius (50F) in the far northwest.