Teachers are calling for pupils who vandalise school property or cause injury during end-of-term pranks to be pursued by the police and courts.

Members of the Scottish Secondary Teachers' Association (SSTA) are moving for criminal and civil actions after a spate of recent incidents.

This week, a first-year pupil at Clydeview Academy, in Greenock, Inverclyde, was taken to hospital after suffering an allergic reaction when senior pupils threw eggs and flour around the cafeteria.

A pupil from Arbroath High School was also hospitalised after being struck in the eye by an egg thrown by graduating sixth-years.

The SSTA's Midlothian branch has submitted a motion to the association's annual congress tomorrow, backing moves to treat such incidents more seriously. The motion states: "The association condemns the criminal behaviour of a minority of pupils on the final day of their school career.

"We support in principle the decision of educational employers and their staff in pursuing criminal and civil actions to hold the perpetrators of such offences to account."

Last night, Alan McKenzie, acting general secretary of the SSTA, said the motion reflected rising concern that end-of-term pranks were getting out of hand.

"It is something we are seeing more of, and it is something that seems to be throwing up more and more serious incidents – and there is a sense that we need to do something about it," he said.

"Some of the behaviour is becoming unacceptable, and appropriate action should be taken by the authorities when it results in injury or damage."

Mr McKenzie said more schools should consider ending the term earlier for sixth-form pupils, a move adopted by Dalkeith High School, in Midlothian, last year.

The SSTA motion was also backed by Unison, the public sector union, which said end-of-year pranks had a significant impact on janitors.

Last year, a Scottish school janitor sued for £50,000 after sixth-form pranks ended with her slipping on steps covered with Vaseline at Galashiels Academy in the Borders.

Dave Watson, Scottish organiser for Unison, said: "The typical jokes we hear about are honey smeared over the banisters or toilet rolls thrown up into trees, which can make a lot of extra work for staff.

"There are also the more dangerous things that we really don't want to see which have ended in injury.

"No-one wants to stop this completely, but there needs to be a sensible discussion between teachers, staff and pupils about what is acceptable."

Eileen Prior, executive director of the Scottish Parent Teacher Council (SPTC) said it would be a shame to criminalise pupils for so-called "muck-up" days.

"Criminal behaviour cannot be defended. However, it would be sad if pupils were to be criminalised for pranks and high jinks," she said.

"A more positive response is to provide avenues for pupils to channel their creativity and energy in more productive ways, involving both pupils and parent councils."

The SSTA's 69th annual congress, which starts tomorrow in Peebles, will also discuss teachers' concerns about the shortage of supply staff and the Curriculum for Excellence.

The union will also debate a call for teachers to spend less time teaching and to be given more protected time for marking and preparation. The motion from the Renfrew branch states: "The duties of teachers have changed. We call - to increase the non-contact time allocation for teachers to allow them to cope with the increasing demand of the curriculum."