“A school has banned triangular flapjacks after a pupil was injured by one. Dinner staff at Castle View school in Canvey Island, Essex, were told to cut the treat into squares or rectangles following the incident. It is understood that the triangular version was banned after one was thrown, hitting a boy in the face.”
http://www.guardian.co.uk/uk/2013/mar/25/essex-school-bans-triangular-flapjacks