I think it would be useful to compare the debate on class size, to the debate on the minimum wage, specifically does class size impact on the quality of learning, and does the minimum wage impact on the level of employment?
The answer for both is yes. If you are from the left and say class sizes impacts quality of teaching but the minimum wage does not impact employment then you are a hypocrite.
Likewise if you are from the right and you say say the minimum wage does impact employment but class size does not impact quality of learning, then you are also being a hypocrite.
Let us take an extreme example for both, to prove out points. Would a child learn better in a class of one, with one on one teaching – or in a class of 1,000 people? Obviously in a class of one (all other things being equal).
Likewise imagine if the minimum wage was $10 an hour and $100 an hour. Could anyone dispute that at $100 an hour, we would have mass unemployment?
So there is no doubt both the minimum wage and class size can have an impact on the number of people employed and the quality of learning. However that doesn’t mean that every change you make has a significant impact, and that degree of that impact may be less than other benefits. Let us start with the argument over the minimum wage.
If the minimum wage goes from $5 to $6 an hour, there may be no impact on employment (as few people may have been employed at that level). Let’s say though it goes from $14 to $15 an hour, which probably will have an impact on employment. Why do the left say this should still happen? They support it, because they argue that if it gets a pay-rise of $40 a week for 150,000 families who have someone on the minimum wage, then that is a satisfactory trade-off for say 4,000 people losing their jobs. It is an issue of what do you see as more important – the level of wages or the number of people in employment.
Now likewise for class sizes. Of course a class of 1 would be far greater than a class of 1,000. But does a class size of say 27 compared to a class size of 25 make a significant difference? The international research is very clear that it has not. Now this is not an argument to have class size of 40 or 50 or 100 because obviously at some stage it will have more of an impact. Hence a private school with a class size of 15 can be better than say a public school with a class size of 30. But that does not mean that a difference between 25 and 27 will make any significant difference.
If it will not make much of a difference, you might say why not then stay with the status quo? Well the reason the minimum wages goes up despite some impact on employment is because it increase wages for those who receive it.
Likewise with class sizes, the benefit of a modest increase, is the funding it frees up for investing in teacher quality – something which has a far greater impact on the quality of learning.
The focus therefore should always be on the trade off. If in the minimum wage debate you focus just on higher wages or just on employment levels, you are missing the picture. Likewise if in the education debate you focus just on class sizes you are also missing the picture.