TARA Shire State College was locked down after a Year 9 girl stabbed another Year 9 girl in the head with a knife.
An altercation broke out between the girls during the lunch break shortly before 2pm on Wednesday.
Education Queensland Darling Downs and south-west Queensland regional director Greg Dickman said a teacher first on the scene performed first aid on the injured student and police and ambulance officers were immediately contacted by the principal.
The stabbed girl was taken to Tara Hospital with serious but non-life-threatening injuries.
She was discharged later that day.
"As a precaution, the school was placed in lockdown until police removed the offending student from the grounds," Mr Dickman said.
"The lockdown was lifted in time for students to leave school safely at the end of the day."
Mr Dickman said a letter was sent to parents yesterday and the school would offer support and counselling to all students, families and staff.
The second girl was charged with unlawful wounding and will be dealt with under the provisions of the Youth Justices Act.
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