Hate crimes and related incidents rose sharply in classrooms across England during last year's Brexit campaign, new police figures suggest.
In May 2016, police reports of hate incidents in schools were up 89% on the same month in 2015, the figures show.
The Times Educational Supplement obtained the data from 30 police forces under Freedom of Information law.
Robert Posner of the Anne Frank Trust UK said racist language had become more accepted since last June's referendum.
Mr Posner, chief executive of the charity, which runs a national programme tackling prejudice-related behaviours among young people, told the TES that the charity had heard more "disparaging" comments in school workshops since the vote.
"Language that we might consider to be either racist or prejudiced has become more normal and more accepted recently," said Mr Posner.
The TES sent freedom of information requests to all 39 of England's police forces.
Of the 32 forces to respond, 30 provided comparable data.
The figures revealed that compared with the same periods in 2015:
- Hate crimes and related incidents were 54% higher in the three months from May to July 2016
- During the summer and autumn terms of 2016, coinciding with the Brexit vote and Donald Trump's US presidential victory, they were 48% higher
There were warnings of increases in bigoted behaviour among pupils at both the National Union of Teachers and Association of Teachers and Lecturers annual conferences last month.
A small survey of 345 ATL members published during their conference showed that more than a fifth of teachers had noticed hate crime or hate speech incidents in their schools during this academic year, and 17% believed it was a growing trend among pupils.
At the time, the union's general secretary Dr Mary Bousted said schools needed to educate children "to build a culture of tolerance and respect" as part of their anti-bullying policies.
"We hope that schools can support staff to educate young people in recognising and challenging hate crimes and hate speech wherever they occur," said Dr Bousted.
At the end of July last year the government announced a review of the ways in which police in England and Wales handle hate crimes and bullying against pupils and staff from minority groups after a sharp rise in the month after the EU referendum.