Education minister Michael Gove attacked a culture of low expectations which says poor children cannot be successful because of their background on Thursday.
Schools can change a child's destiny and many are proving this through hard work and good teaching, he said.
He launched a stinging assault on union leaders and local councils, accusing them of putting their own interests ahead of those of children.
Gove said: "Despite the evidence that other nations are closing the gap between rich and poor through great state schooling, some in this country still argue that pupil achievement is overwhelmingly dictated by socio-economic factors.
"They say that deprivation means destiny - that schools are essentially impotent in the face of overwhelming force of circumstance - and that we can't expect children to succeed if they have been born into poverty, disability or disadvantage."
Gove, addressing private school heads at a conference at Brighton College, said he did not accept this, and that there are a growing number of schools "proving that deprivation need not be destiny - that with the right teaching and the right values they can outperform everyone's expectations".
Research has suggested there are more than 440 secondary schools where the average GCSE point score for children on free school meals - a key measure of poverty - is higher than the national average for all children.
"What they share is an unwavering, unapologetic focus on standards," the minister said.
"Led by inspirational heads and teachers, every day these schools are proving the pessimists and fatalists wrong."
Gove's attack comes weeks after a union leader warned that UK schools are segregated along class lines, leaving the poorest children struggling to achieve against poverty and deprivation.
Dr Mary Bousted said stratified schools are "toxic" for deprived youngsters as it means they fail to learn important qualities such as aspiration and effort from richer classmates.
The general secretary of the Association of Teachers and Lecturers told its annual conference last month that it is the coalition Government's "dirty little secret" that their education cuts and reforms are making the lives of the poorest children tougher.
She raised concerns that schools are held up as the scapegoat for educational failure, accusing ministers and Ofsted of "seeking to wash their hands, like Pontius Pilate" of the problem.