The boy, aged 17, suffered a single stab wound in an alleyway close to Poole High School off Wimborne Road just after 15:00 GMT on Thursday.
He was taken to hospital following the attack where his condition was described as not life-threatening. He has since left hospital, police said.
The boy has also been charged with possession of an offensive weapon.
He is due to appear in Bournemouth Youth Court on 16 February.
A 15-year-old boy has been charged with assault after a teenage boy was stabbed in Poole.