About 2,500 teachers rallied and marched in Regina on Thursday during the second day of a two-day strike to back contract demands.JENNIFER GRAHAM
Frances Woolley is a professor of economics at Carleton University, where she teaches public finance.
Ontario is a great place to study teachers' strikes.
First, the province has had plenty of them -- at least 101 between1975 and 2005.
Second, Ontario strikes usually take place at the board level. Some school boards are affected, some aren't. This makes it possible to contrast students who have experienced a teachers' strike with those who have not.
Third, Ontario has province-wide tests -- the Education Quality and Accountability Office (EQAO) assessments -- in grade 3 and grade 6. These tests can be used to assess the educational performance of students who experienced a teachers' strike.
University of Toronto economist Michael Baker brings these three things together, in a new paper examining the impact of primary teachers' strikes on students' EQAO test results over the 1998 to 2006 period.
Many factors affect a student's EQAO test scores: family background, a child's innate ability, "school spirit." Compared to these other factors, teachers' strikes are unimportant. When Professor Baker looks at grade 3 EQAO test results in isolation, he finds no statistically significant differences between the scores of students who have experienced a strike, and those who have not. The same is true in grade 6. Teachers' strikes cannot explain any significant amount of the variation in grade 6 EQAO test scores.
But what if you could completely control for family background, innate ability and so on? Would teachers' strikes matter then?
Prof. Baker begins with the premise that a student's family background and innate ability do not change much, on average, between grade 3 and grade 6. Yes, capable students will generally do better on the grade 3 test, and better on the grade 6 test. But if we look at the difference between grade 3 and grade 6 test results, factors such as family background and ability should cancel out.
When Professor Baker looks at the change in test scores over time, he finds some evidence that strikes matter -- at least in the short run. Students who experienced a ten or more day strike in grade 6 did worse, relative to their grade 3 results, than students who did not. The effect was especially pronounced for math, where grade 6 test scores of strike-affected students fell by 0.10 points on the EQAO's 1 to 4 scale. For an average student, that would translate into a 3.8 per cent decline in their grade 6 math result. For writing and reading, the effect of long strikes was still negative, but smaller -- the equivalent of a one to two per cent reduction in an average student's grade 6 EQAO test score.
Yet Professor Baker's results also suggest that the negative impact of strikes is short-lived. Strikes in grade 5, even long ones, have little impact on the grade 3 to 6 growth in EQAO test scores. Even strikes occurring in grade 6 have little significant impact, as long as they last less than ten days.
So Saskatchewan students and parents can relax -- even if this strike lasts a few more days, it is unlikely to have a long-run impact on students' achievement.
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