In the Arctic tundra a creature called the lemming undergoes wild fluctuations of population. Every few years, these small rodents experience a population boom, followed by a crash. At the height of the boom, lemmings carry out their well-known behavior of following one another into the ocean to drown. Ecologists seeking to understand this looked at predator/prey cycles, weather, and nutrients. They were surprised to learn that the critical factor was the availability of calcium, which gets depleted as the population of lemmings expands - and calcium becomes concentrated in their bones. When calcium gets scarce, the plants have trouble growing, and the lemmings run out of food. When food becomes scarce, the lemmings set out in all directions, even across water. Although the vast majority will drown, some small number may succeed in colonizing remote locations that have not been overgrazed.
It matters a great deal what factors we consider when investigating an ecosystem, because how we understand what is happening could be greatly influenced by what we consider, and what we choose to exclude. We want to make the system as simple as possible so as to be able to understand the variables, but we must consider all the relationships that might matter, because until we investigate, we cannot be sure which will be most important.
With our schools, we have identified a problem. Students are not performing at the levels we desire, and too many are dropping out. There is a problem with the way we are looking at this ecosystem, however. In the materials publicizing the latest education reform propaganda vehicle, Waiting for Superman, it is clear that, according to the “experts” in this film, poverty should not matter, family background, violent neighborhoods, all of this is of minimal importance compared to the all-important teacher.
There are lots of reasons why it would be convenient for this to be so. If all that matters is the effectiveness of our teachers, we can improve our schools significantly by getting rid of poor teachers and making those that remain even more effective. We can incentivize higher test scores and get teachers to prioritize instruction that will drive them upwards.
But there is a problem with this. It defines the ecosystem in such a way that the only relationship that matters is the one between the teacher and student. But there are many other factors that influence student performance. What if the scientists studying the lemmings decided that the only thing that mattered was the relationship between lemmings and their main predator, the arctic fox? It would be convenient. And in fact it looks as if the numbers of foxes rises as the number of lemmings rises, so this could be a viable theory. But this would miss the actual relationship that turned out to be the crucial one.
In the case of our schools, similar to the Arctic circle, there is a nutrient cycle that is driving student performance. There are clear and consistent scientific data that indicates that poverty is the critical factor affecting student performance.
As Stephen Krashen pointed out in this space a few months ago,
American students from well-funded schools who come from high-income families outscore all or nearly all other countries on international tests. Only our children in high poverty schools score below the international average. The US has the second highest percentage of children in poverty of all industrialized countries (22.4%, compared to Sweden's 2.6%) which of course pulls down our overall average. The success of American children who are not in poverty shows that our educational system has been successful; the problem is poverty.
This is more pertinent than ever, as we see the number of children living in poverty steadily climbing, at the same time attacks on teachers as the source of the problems in schools reach a fever pitch.
This does not mean we should ignore teacher effectiveness. We should pursue policies, such as improved evaluation practices and time for collaboration, that help make teachers more so. It is clear that a great teacher can make a big difference, and we need to do everything we can to create the conditions to support and spread excellence. However, we must look at our schools as ecosystems, look carefully at all relationships in this system, and be skeptical about those who offer simplistic models that exclude critical factors from consideration.
What do you think? Are teachers the key variable affecting student performance? Or does this miss other, more important factors?
Image used under Creative Commons license, by kgleditsch.