electric, i work for the local education authority in one of the london boroughs where there has been a recent high profile muder invoving a knife. i strongly advise u to first approach the the headteacher, and if u get no joy, secondly contact your local eduaction dept and ask to speak to the link inspector for your school. knives are for kitchens only, not for kids to be carrying around on the street for 'cookery lessons'. someone, somewhere in the school authority needs to be strung up!