Huw Tudur will use his presidential speech to the annual conference of UCAC, the Welsh-speaking teachers' union, this weekend to demand a more flexible curriculum for Welsh schools.
He told The TES: "The curriculum doesn't give teachers enough opportunity to teach about the history of Wales. We'd like to see Welsh history at its core, as a framework which every subject would work around.
"I don't feel the national curriculum gives us the flexibility to find out who we are. You need to give children memories, otherwise we won't have a nation."
Mr Tudur's speech, delivered entirely in Welsh, will be backed by Moelwen Gwyndaf, who was elected as the 4,700-member union's general secretary earlier this year. Ms Gwyndaf said vocational courses, in particular, often failed to reflect the Welsh heritage sufficiently.
"We'd like to see syllabuses that are Welsh in ethos, not just translated from the English," she said.
The conference will also provide a forum for members to discuss the national workload agreement. Like the National Union of Teachers, UCAC refused to accept the agreement's terms.
The two-day conference, held in Carmarthenshire, will be attended by Jane Davidson, Welsh Assembly minister for education and lifelong learning.