Far from boosting the 3Rs, cutting back on history and geography could hinder children's literacy.
The claim is made by the teachers and academics of the Historical Association, which has reacted to last week's primary curriculum slim-down with fury.
The Geographical Association greeted the Government's move "with incredulity and outrage".
There are now only three years of full national curriculum study in geography and history, from 11-14. The two subjects had already become optional for older students thanks to Sir Ron Dearing's 1994 curriculum review.
"This could make decent literacy harder to achieve because literacy needs context," said Roy Hughes, chair of the HA's primary committee. "There is also a danger that history will become a middle-class ghetto. The children who need this enrichment the most could end up with a diet only of the basics."
The HA also warns that the Government's surprise move will leave the curriculum in the hands of the Office for Standards in Education until 2000, when the whole school syllabus is to be overhauled.
Christine Counsell, from the HA and the University of Cambridge school of education, said that the slim-down would deprive pupils of cultural understanding and undermine the national curriculum.
"Most worrying of all," she said, "it ignores the close relationship between history and English. This relationship makes the sidelining of history counterproductive in the pursuit of literacy."
She believes that primary pupils have made great strides through learning how to structure their writing in history lessons and that "removing the statutory framework will undermine such gains.
"To teach pupils to describe and evaluate the story of the past is to develop their ability to write fluently and with precision. Teaching them to analyse a range of sources is to deepen their understanding of text."
Grant Bage, also a Cambridge lecturer, warned that suspending the curriculum requirements will "drastically weaken history's contribution to the development of citizenship and cultural literacy.
"It is understandable that primary teachers should want to reduce their coverage. Their workload was excessive. But why have we gone from one damaging extreme to another?" letters, page 22