Samurai swords, axes and air guns are among the 2,579 weapons seized from schools in England and Wales, Freedom of Information requests have shown.
Press Association analysis of data from 32 of the 43 police forces in England and Wales said the weapons had been found in two years to March 2017.
Police chiefs said there had been a “worrying” increase in young people carrying knives.
There are about 25,850 schools in England and Wales.
Heads said children’s safety was their top priority and that schools worked closely with police to protect pupils.
In 2016-17 alone, 1,369 weapons were found – a rise of almost 20% on the previous year.