Tuesday, November 14, 2006

Class Size

Classes should be no more than 15 students. Here's the research. Don't let anyone tell you class size doesn't matter.


Anonymous said...

You're cherry-picking research, as you often do (sad to say), to support what you already believe. One could just as easily and quickly find counter-evidence.

Ben Guest said...

Counter-evidence to what? Class size not making a difference in instruction? I defy you to find as in-depth a study as the one I've cited that shows class size doesn't make a difference. And is that really your opinion? For how many years have you taught K-12?

Anonymous said...

Four years, plus teaching at the college level.

See commentaries by Jay Greene of the Manhattan Institute, I believe. Also, see below:

The Class-Size Myth
New York Sun Editorial
May 13, 2005

Both Mayor Bloomberg and the City Council speaker, Gifford Miller, apparently having done the electoral arithmetic and concluded that the best interest of teachers unions and the false hopes of parents trump the substance of education reform, are going into this election in support of one of the discredited ideas that smaller class sizes are a key to educational performance. The mayor, in his executive budget last week, proposed spending $10 million to reduce class sizes from kindergarten through third grade. Mr. Miller, who is running for mayor, jumped on the bandwagon on Tuesday with his own "17 Seats" initiative to reduce classes all the way through middle school.

It's too bad the bandwagon isn't going anywhere. There's no convincing evidence that reducing class size improves student performance in any but the most extreme cases, where class sizes are more than twice the New York City average or in special education. Proponents of class size reduction like to point to several experiments over the past two decades that purport to show that smaller classes work. But a careful look at these studies discloses methodological problems that raise questions about the results. And an international study from the Organization for Economic Cooperation and Development last year couldn't find any meaningful connection between class size and student performance.

If anything, cutting class size may actually hurt achievement. California rolled out sweeping class-size reductions in the mid 1990s. Golden State test scores have improved somewhat since then, but the gains have been uneven and aren't related to changes in class size. That's because to reduce class size, you have to hire more teachers. One 2002 study from the Public Policy Institute of California found that in the rush to do so, districts had to scrape the bottom of the barrel to find enough warm bodies to stand in front of classrooms. New York would be under the same pressures. By the City Council's count, Mr. Miller's "17 Seats" plan would require 2,035 new teachers by fall 2006. No one has yet publicly stated how many new teachers Mr. Bloomberg's plan would take.

Even if they aren't competent at teaching, those bodies can still join teachers unions. That helps explain why unions are so supportive of class-size reduction, particularly if a debate about class sizes distracts from the more important discussion about teacher quality, a real determinant of educational success. The fact remains that class sizes have been steadily decreasing for the past half century, even as educational quality has also been on a downward trend.

Messrs. Bloomberg and Miller aren't just trying to appease teachers unions; class-size reduction is popular with a lot of parents. That's understandable. Some parents might find the idea of little Johnny being one of only 17 children in a class more appealing than the idea of Johnny sharing a teacher with 21 other kindergartners. Others might be more focused on the qualifications of the teacher. Well, why not let them choose, with a voucher that allows them to select a school based on class size, teacher quality, or any other factor they think is important? We don't have a problem with small classes. Politicians who falsely present class-size reduction as a panacea are another matter. They may buy off the teachers union, but there's no reason to believe either of these expensive plans will do anything for the vast majority of students.

Ben Guest said...

Have you read the study I linked to? Clearly not. Go back and read it. Again, I defy you to find another study that is as comprehensive.

If you taught K-12 for four years than you understand that class size is the key factor in education. A class of 30 and a class of 10 are two completely different experiences. The class of 10 learns much more than the class of 30. I've taught classes as small as three and as large as 40. The class of three learned much more than the class of 40.

I do agree with the editorial that to reduce class size without an improvement in teacher pay means that you will simply scrape the bottom of the barrel of teacher quality. But this is not an argument against reducing class size, it is an argument against hiring incompetent teachers.

The study I linked to addresses this (again, read it before criticizing it) with the numbers on teachers' aides. Adding a teacher's aide does nothing to improve instruction in the classroom. But two classes of 14 students with two quality teachers is much better than one class of 28 and one quality teacher. To think otherwise, especially if you are a K-12 teacher, is simply not credible.

Anonymous said...

The article to which you link implies that the benefits of reduced class size really accrue from the decreased work load on teachers. I suppose that, as with any job or task, when one has less to do, one is able to put more energy, enthusiasm, attention, and creativity into the few tasks one has. Duh. But let's operate in the sphere of reality. In a prior post and discussion on teacher pay, you concede that the benefits to increased teacher pay would only result at very high levels of pay, and that this level of pay was not realistic. (Also, I might note, you spoke then of increased pay as THE key to improved student performance, and here you call class size THE key factor in education). The same applies here. Maybe decreased class size has benefits - hell, let's just give every student an individual tutor. This would surely result in improved performance. But in a system with finite resources, those resources and our attention must be focused on those strategies which would yield the greatest benefits in light of these limited resources. Increasing teacher pay to astronomical levels, and reducing class size to the optimal 1:1 ratio (or even 1:15) is not realistic given our already way too expensive education system. I might be in favor of dedicating more resources to these strategies (increased pay, smaller class sizes), but given average per pupil spending in districts with horrible outcomes, these resources, in my opinion, must be redirected from other spending, not added to our already bloated education budgets. In NJ, for example, the WORST districts spend the MOST money in the state, and have NOTHING to show for it. So, reduced class size might improve outcomes, six-figure starting teacher salaries might, teachers with a minimum PhD might, one-on-one tutoring from Nobel laureates might, lots of things might . . . but live in reality.

Ben Guest said...

You're changing the topic. The point is that reducing class size improves student learning. That is a point that you seem to agree with. As with increasing teacher pay, I never said reducing class size was realistic, just right.

As for our education system being too expensive, you are wrong. Compared to most industrialized nations we spend far less on our children's education. We have an education system done on the cheap and that is one of the reasons why we have a failed education system.

steven p said...

"If anything, cutting class size may actually hurt achievement."

What a bizarre statement. It's like claiming that exercise is bad for our health. And it could be if by exercise we mean juggling chainsaws or swimming with sharks. In the same sense, small class sizes could hurt achievement, I suppose, if the teacher were a drug dealer or pedophile, which sometimes happens... but that is another issue.

To anonymous, and anyone else who might question the validity or this study, first read it. Then read what people say about it. The study is incredibly comprehensive, and unlike most studies, it is careful not to compare apples to oranges. The study compares urban students in large classes to urban students in small classes, rural students in large classes to rural students in small classes, high income students in large classes to high income students in small classes, etc. Studies don't typically do this. Those advocating small classes will typically compare small classes in private schools to large classes in low-income public schools, and of course the students in the small classes do better. Similarly, those who argue that class size does not matter will compare small low-income students in small classes to high income students in larger classes. Again, the comparison isn't fair.

More importantly, this study defines class size as, literally, class size. Many studies (and school districts) will make claims about class size when they are actually using numbers about student/teacher rations. The catch is that in a school, principals, coordinators, consultants, teacher's aides, reading specialists, etc. are all considered "teachers" so the numbers are skewed. Someone can look at a school that "reduced class sizes" and not see a significant change in student achievement because class sizes weren't actually reduced--the school just hired more people with education degrees and put them in an office somewhere. This is how Utah makes a claim of 20:1 student teacher ratios when anyone who has taught in Utah knows that the average class size is closer to 25-30 students. I taught in a school in Tennessee that was incredibly burdened with "educator" and had a student teacher ratio of 13:1, while actual class sizes rarely dipped below 25.

I understand that "anonymous" was probably on the high school debate team and probably majored in political science in college and so has been trained to argue a point even if the point is absurd. Read the study done in Tennessee, read other studies (don't rely on analysis from a reporter for the Sun) and make informed, genuine arguments.

Sorry Ben, this is your blog, but after reading that statement (small class sizes harmful!) I had a hard time falling asleep. What an incredibly ignorant (and even harmful) statement to come from someone who claims to have taught. I know I am getting personal, but this particular political issue is personal to me and anyone else who has taught or who has children in school (or both). Besides, no harm in making mean statements about an "anonymous" person.

Anonymous said...

I didn't change the subject, I was providing another example of one of the problems I see in your analysis on class size. If you're just making points without considering context, that is, the realities on the ground, you're making pointless posts. In a vacuum, perhaps reducing class size modestly improves learning, but given the high cost, limited funds, and limited pool of people desiring to be teachers, it's not realistic, just as your contention about teacher pay is (as you admit) not realistic. Why make commentaries on policy issues if you're merely playing in fantasyland?

And I fail to see how the argument that reducing class size could harm achievement is bizarre. Again, this contention is made within the sphere of reality. There are only so many people willing to teach - if you require many more quickly or even over time, as with anything else, the quality will suffer. Again, reality folks. By the way, wasn't on the debate team (hs didn't have one), didn't major in political science, and was and am indeed a teacher.

And read the following by Jay Greene. It's a nice summary of the points, and he says it better than I can.

The class size myth
Jay Greene

Just about everybody agrees that smaller classes produce better results. This view was captured crisply in a Chicago Tribune feature story on schools: "The advantages of small classes seem intuitive; who wouldn't want children to learn in a small class? Parents crave them, teachers love them, and policymakers push for them."

As popular discontent with the state of education has grown, class sizes have emerged as a key political issue for both parties. The National Education Association has been particularly aggressive, supporting "a class size of fifteen students in regular programs and even smaller in programs for students with exceptional needs." Given that shrinking class sizes means hiring more teachers, and thus putting more money into the pockets of teachers unions, it is hardly surprising that unions are the loudest supporters.

Unlike other myths, this one isn't totally baseless. Research suggests there may be some advantages to smaller classes--though if so, the benefits are modest and come at a very high price tag. And whether this research is actually correct is a matter of debate. So the strong claims for class size reduction made by political activists are not at all justified.

The centerpiece of class-size research was the STAR project, a 1980s experiment conducted by the state of Tennessee. Students were randomly assigned to one of three types of classes as they progressed from kindergarten through third grade. The first type was a regular-sized class of around 24 students with one teacher. The second option was a regular-sized class with a teacher plus a teacher's aide. The third alternative was a small class of around 15 students with one teacher.

The study found that students in the small classes showed a one-time benefit in test scores as compared to students in regular-sized classes (the teacher's aide resulted in no significant difference). The increase, however, was not large--the equivalent of an eight-percentile-point improvement in performance for a student starting in the middle of the pack. But follow-up research found that 44 percent of students in STAR's small classes took college entrance exams, compared to 40 percent among regular-class students--not so trivial a difference. If we could be reasonably sure that this increase resulted from smaller classes, and could be replicated on a large scale without sacrificing other educational priorities, then class-size reduction would be solidly supported. Unfortunately, the evidence does not allow us to reach those conclusions.

There were a number of shortcomings in the STAR program's implementation that raise doubts about the accuracy of its findings. Most significantly, students weren't tested when they entered the program--so we can't confirm that the three groups started out at the same level as the experiment began. There is no way to know if the project's random assignment method was accurate, and thus no way to be certain that differences observed among the groups weren't there from the beginning.

There is reason to be suspicious because of an anomaly in the research findings: If smaller classes really do improve student performance, we would generally expect to see these benefits accrue over time. But instead, the improvement in STAR test scores was a one-time event. This is unusual and unexpected. Considering that the project's supposed benefits were moderate to begin with, this raises serious doubts about whether the STAR results should lead to policy prescriptions--particularly since evidence on large-scale class size reduction is much less encouraging.

In California, the state appropriated $1 billion in 1996 to reduce elementary school class sizes. When California's test scores rose, advocates of smaller classes held up their program as a model. The reality, however, wasn't so clear. A RAND Corporation study concluded that California students who attended larger elementary school classes improved at about the same rate as students in smaller classes. Though California's overall educational performance went up, it did not seem to be due to smaller classes. (The state had also undertaken a number of other major education reforms at the same time it was reducing class sizes.)

Even if class size reduction does improve performance under optimal conditions in a small, controlled experiment like the STAR project, labor pool problems may prevent this from being reproduced on a large scale. Replicating the benchmarks of the STAR project would entail hiring almost 40 percent more teachers nationwide. Digging that deeply into the teacher labor pool would require accepting a lower quality of hire, likely bringing disappointing results.

And the financial costs of reducing class sizes on that scale would be exceptionally high--$2,306 per pupil according to calculations by Caroline Hoxby of Harvard University. There is only a finite amount of money available, so every dollar spent on class size reduction is a dollar that will not be available for salary increases, books, equipment, or the implementation of other reform policies. This will be true no matter how much money a school system has. Given that other reform strategies are more promising and less costly, the modest benefits of class size reduction simply can't justify the very large sacrifices that would have to be made.

Anonymous said...

And about the cost of education: forget about comparing to other nations; it's not necessary. There's enough variation in spending here in the US so can avoid the problems of cross-national comparisons. Just compare the results in high cost districts here in US to lower cost districts here. See NO correlation between spending and outcomes. To contend otherwise really is foolish. So many districts spend so much more than others and have little to show for it. Arguing that more money solves social problems like poor education is Carter-era thinking.

Ben Guest said...

My refrain, as it was and as it always shall be, is: If money doesn't matter why do rich people spend so much on their children's education?

As for small classes not being realistic, okay. Lots of things I think about are not realistic. I think about a country that provides an equal education for all. That is not realistic, but here I am, in the trenches, working towards that goal...