The teenager, who cannot be named for legal reasons, has been on trial at King's Lynn Crown Court after denying attempting to murder the fellow pupil at Thorpe St Andrew School on March 11.

Stephen Rose KC, who is defending the boy, described the case as "a very serious and troubling" one as he began his closing speech.

Mr Rose said the boy had admitted wounding with intent and possessing a bladed object but had not intended to kill his victim despite planning an attack at the school.

The knife the boy used in the attack (Image: Crown Prosecution Service)

Thorpe St Andrew School, where the girl was stabbed on March 11 (Image: Denise Bradley)

"Evidence of planning is not evidence of intention," he said. "The problem is that human beings can change their minds.

"The fact we've expressed a strong opinion about something on Monday does not mean we'll feel the same on Friday."

Mr Rose said the boy had accepted responsibility for his........

© Norwich Evening News