Education Minister Patrick Rouble refuses to set targets for improving high school graduation rates in the territory and cannot guarantee more accurate statistics with respect to those rates.

For a second sitting day in a row Monday, the Education minister faced a barrage of criticism from Liberal opposition MLAs over dismal graduation rates noted by Auditor General Sheila Fraser in her less-than-stellar appraisal of the Yukon's education system.

At the end of January, Fraser reported only 40 per cent of first nations students graduate from Grade 12 and just 58 per cent of all Yukon students reach that milestone.

But instead of publishing these figures, the department presents significantly higher statistics based on the number of students entering Grade 12, and those who successfully complete the year.

According to this calculation method, the department reported in its 2007-2008 annual report that 89 per cent of first nations students graduated while 92 per cent of all Yukon students successfully completed high school.

During Monday's question period, successive Liberal MLAs repeated Fraser's analysis that these data are "misleading" and called for Rouble and his department to change its ways.

"The credibility of the minister has been challenged by the Auditor General. Yukoners need to know the facts; they need to know the information in the annual report is true," said Liberal Education critic Eric Fairclough.

"He needs to accept the responsibility, apologize to Yukoners and assure them that the reporting techniques will not be happening again."

But no apology, nor a methodology as to how future graduation rates might be calculated, was offered by Rouble.

Next to take a crack at the Education minister was Vuntut Gwitchin MLA Darius Elias. The Liberal wanted to know what changes are taking place to improve outcomes for first nation students.

"There are numerous different initiatives that have begun," said Rouble.

"Some of these include school growth planning, leadership programs, resiliency issues, as well as changes in the classroom - changes in curriculum, changes in instructional styles."

However, this answer did not satisfy Elias.

"The fact of the matter is that we need more of our Yukon children with diplomas in their hands," he retorted. "(40 per cent first nations graduation rates) is a dismal failure ... and the minister is the leader.

"That responsibility rests at his feet, and this minister suggests that we deal with the problems by continuing to talk and announcing another study."

When Liberal Leader Arthur Mitchell took his turn at questioning Rouble, targets and timelines for improving Yukon graduation rates were what he wanted.

Through two supplementary questions, Rouble dodged the Liberal leader's request and attempted to score a knockout blow by reminding Mitchell of comments he had made during a local radio interview.

"I won't put words in the member opposite's mouth," said Rouble. "Instead, I will remind him what he said on Feb. 9 on CBC, where the member opposite said, 'I learned there was a commitment from senior staff in the department, starting with the deputy, to effect change.'"

Mitchell made these remarks following a day-long hearing by the Public Accounts Committee (which he chairs) on the findings in Fraser's report.

Following question period, Rouble declined to speak to the media.