Police are being called to deal with knife offences at West Midland schools an average of more than two times a week.
Nearly 250 incidents involving knives have been recorded at 192 schools in the region since 2004, according to West Midlands Police.
In the first half of this year alone there were 45 cases where a knife, sharp instrument or razor was used in or outside a school.
Most were at secondaries, but a significant number were primaries. A quarter resulted in a person being injured.
Lib Dem Shadow Education Secretary Sarah Teather expressed alarm at the findings and warned of a knife "arms race" among youths.
"These figures are horrifying and demonstrate the disturbing extent of the knife problem in West Midland schools," she said.
"Where there is a culture of fear in a school already it can so easily escalate - much like an arms race."
Shadow Education Secretary David Willetts added the figures highlighted a need for "more police action and more power for schools".
"School children should not be living in fear of knives. They have no place in or near our schools. But it is getting harder and harder for schools to maintain order," he said.
The National Union of Teachers called for airport style checks to be introduced to protect pupils and teachers at problem schools.
"It is very worrying to see the scale of the problem in that offensive weapons are being carried by students against the school rules," said Brian Carter, the NUT's Midland regional secretary.
"We need to find a way of enforcing school rules without leading to further conflict or confrontation. If we could target the schools where there is a particular problem one could look at machinery that could detect metal in the same way as airports."
Figures show there were 96 offences involving a knife or sharp implement at 70 schools in 2004. Just under 40 were at secondaries and 13 were at primaries. In a further 38 cases the type of school was not stated.
The remaining eight were at residential, special, community or leisure centres or sports colleges.
In 2005 there were 103 knife offences at 87 schools - 36 at secondaries and 20 at primaries and a further 45 where the school type was not stated. Of the 45 knife offences this year, 15 were at secondaries, six at primaries and in 21 cases the type of school was not noted.
The figures come amid increased concern over young people carrying knives.
Last month Education Secretary Alan Johnson told The Post that tackling a culture in which it's seen as "cool" to carry knives was the challenge facing teachers, parents and Ministers. ..SUPL: