The province should also aim to reduce pension contributions, since it matches what the teachers pay in, and ask school boards for a review of benefits, the economist said.
"The typical teacher retires at 59, having worked for 26 years, and then collects a pension for 30 years," Drummond said in his report. "A higher average retirement age would reduce the need for lower benefits in the future."
Drummond also found the government needs to address the "overproduction" of teachers, given that the number of new teachers now exceeds that of new retirees by 7,600 a year.
When it comes to Premier Dalton McGuinty's flagship program, full-day kindergarten, Drummond agrees there are proven benefits. But, he said, "in the current fiscal climate, the commission is concerned that the timing is inappropriate."
He would like to scrap the plan — which will cost $1.5 billion a year when fully implemented — but said that if the government insisted on going ahead it should at least delay full implementation to 2017-18 from 2014-15.
Costs could be further reduced by bringing in one teacher for about 20 students instead of one teacher and an early childhood educator for 26 students.
The Liberals should also try to offset some costs by getting commitments on wage increases, class sizes and non-teaching staff from school boards and unions.
Class sizes should be capped at 23 students instead of 20 in primary school, Drummond recommends. Average class sizes in Grades 4 to 8 should be increased from 24.5 to 26 and secondary schools should increase average class sizes to 24 students from 22.
Non-teaching positions, the report argues, should be reduced by 70 per cent.
Finance Minister Dwight Duncan already said he wouldn't scrap full-day kindergarten but on Wednesday hinted he was also unlikely to consider a revamp of the program, as Drummond suggested.
"That's in the mix ... but we've said that full-day kindergarten is the one thing we want to protect, and our objective would be to protect it as we established it," Duncan said after the report was made public.
Progressive Conservative Leader Tim Hudak, who initially called the program a frill but later backed it during the election campaign, sided with Drummond, saying that if the Liberals couldn't bear to let it go they had to put something else on the chopping block.
"I know that's not great news for the people across the province who were looking forward to that program, but it's time somebody actually did some straight talking," said Hudak.
"I just don't see how we can go forward."
NDP Leader Andrea Horwath disagreed, saying that if the point of the report was to ensure all money being spent led to future improvements, all-day kindergarten and investment in post-secondary education are "things that actually, invest in our future."
Drummond did not touch on the issue of whether the province should continue to fund two school systems — Catholic and a public — saying those were constitutionally dictated.
But he did say students should also be discouraged from participating in a fifth year of high school, known as a "victory lap" by those who've completed Grade 12 but opt to take more classes to get additional credits or improve their grades.
If students want to do so, school boards should be allowed to charge a fee, Drummond suggested. He also proposed fees for certain school bus routes.
The Ontario Secondary School Teachers' Federation called several of Drummond's recommendations "extreme measures which would be detrimental to student success," and warned it would consider their implementation as "extremely confrontational."
The union representing elementary public school teachers, for its part, said it was confident McGuinty would "do the right thing" and reaffirm his government's commitment to education in the face of Drummond's proposals.
Drummond also provided several recommendations for post-secondary education, namely, to create a clear distinction between college and university degrees and reduce duplication by preventing colleges from bringing in any new degree programs — although existing ones can be grandfathered.
After two years of study, college students who meet certain academic criteria could transfer to the university system.
Universities should also seek to provide more experience-based learning such as internships, independent study and study abroad programs, as well as examine whether some four-year programs could be turned into three by working throughout the summer.
The government, meanwhile, should consider better ways to target financial assistance to low-income students and establish a single pension fund administrator for all university and college pensions.
If his overall recommendations can't keep spending in post-secondary education under control, Drummond said, the Liberals should eliminate their newly minted 30 per cent tuition rebate.
Drummond also called for a review of special education programs, as well as the consolidation of schools for the deaf from junior kindergarten to Grade 12 in one location.
First Nations education desperately needs more funding, he said, and that money should come from negotiations with the federal government. If a deal cannot be reached, Drummond said, the province should provide the funding itself.
All these measures should help limit spending growth for education to one per cent a year to 2017-18, or $1.6 billion more, while post-secondary could grow by 1.5 per cent, or $700 million, he added.
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