ACT Education Minister Yvette Berry is under fire, after saying NAPLAN data was used to "point out dumb students".
Thousands of students across Canberra will sit the national literacy and numeracy test this week.
But Ms Berry told WIN News: "Data from NAPLAN is used to create league tables, and then belittles school communities and sort of points out dumb students, if you like, compared to the smart students."
ACT opposition education spokeswoman Elizabeth Lee described the comments as "offensive".
"NAPLAN isn't an excuse to put insulting labels on our students, it's an opportunity for teachers to assist our students in their learning," Ms Lee said.
Ms Berry apologised and said she "used a poor form of words".
"I have not and never would call any person dumb," she said.
"The point I have consistently made is that NAPLAN in its current form has too many students forming negative perceptions of themselves and their schools.
"Since I became Education Minister I have continually worked to try to move NAPLAN away from its high-stakes nature - particularly the stress and anxiety it can cause."