It’s summer in Baltimore. The temperatures are beastly, the humidity worse. I grew up in Washington, DC, which has the same weather. We had no air conditioning, so summers could be torture. No one could sleep, so we all walked around like zombies, yearning for fall.

Today, however, summers in Baltimore are completely bearable. The reason, of course, is air conditioning. Air conditioning existed when I was a kid, but hardly anyone could afford it. I think the technology has gradually improved, but there was no scientific or technical breakthrough, as far as I know. Yet somehow, all but the poorest families can afford air conditioning, so summer in Baltimore can be survived. Families that cannot afford air conditioning need assistance, especially for health reasons, but this number is small.

The story of air conditioning resembles that of much other technology. What happens is that a solution is devised for a very important problem. The solution is too expensive for ordinary people to use, so initially, it is used in circumstances that justify the cost. For example, early automobiles were far too expensive for the general public, but they were used for important applications in which the benefits were particularly obvious, such as delivery trucks and cars for doctors and veterinarians. Also, wealthy individuals and race car drivers could afford the early autos. These applications provided experience with the manufacture, use, and repair of automobiles and encouraged investments in infrastructure, paving the way (so to speak) for mass production of cars (such as the Model T) that could be afforded by a much larger portion of the population and economy. Modest improvements are constantly being made, but the focus is on making the technology less expensive, so it can be more widely used. In medicine, penicillin was invented in the 1920s, but not until the advent of World War II was it made inexpensive enough for practical use. It saved millions of lives not because it had been invented, but because the Merck Company was commissioned to find a way to make it practicable (the solution involved growing penicillin on rotting squash).

Innovations in education can work in a similar way. One obvious example is instructional technology, which existed before the 1970s but is only now becoming universally available, mostly because it is falling in price. However, what education has rarely done is to create expensive but hugely effective interventions and then figure out how to do them cheaply, without reducing their impact.

Until now.

If you are a regular reader of my blog, you can guess where I am going: Tutoring. As everyone knows, one-to one tutoring by certified teachers is extremely effective. No surprise there. As you regulars will also know, rigorous research over the past 20 years has established that tutoring by well-trained, well-supervised teaching assistants using proven methods routinely produces outcomes just as good as tutoring by certified teachers, at half the cost. Further, one-to-small group tutoring, up to one to four, can be almost as effective as one-to-one tutoring in reading, and equally effective in mathematics (see www.bestevidence.org).

One-to-four tutoring by teaching assistants requires about one-eighth of the cost of one-to-one tutoring by teachers. The mean outcomes for both types of tutoring are about an effect size of +0.30, but several programs are able to produce effect sizes in excess of +0.50, the national mean difference on NAEP between disadvantaged and middle-class students. (As a point of comparison, average effects of technology applications with elementary struggling readers average +0.05 in reading, and in math, they average +0.07 for all elementary students. Urban charter schools average +0.04 in reading, +0.05 in math).

Reducing the cost of tutoring should not be seen as a way for schools to save money. Instead, it should be seen as a way to provide the benefits of tutoring to much larger numbers of students. Because of its cost, tutoring has been largely restricted to the primary grades (especially first), to perhaps a semester of service, and to reading, but not math. If tutoring is much less expensive but equally effective, then tutoring can be extended to older students and to math. Students who need more than a semester of tutoring, or need “booster shots” to maintain their gains into later grades, should be able to receive the tutoring they need, for as long as they need it.

Tutoring has been how rich and powerful people educated their children since the beginning of time. Ancient Romans, Greeks, and Egyptians had their children tutored if they could afford it. The great Russian educational theorist, Lev Vygotsky, never saw the inside of a classroom as a child, because his parents could afford to have him tutored. As a slave, Frederick Douglass received one-to-one tutoring (secretly and illegally) from his owner’s wife, right here in Baltimore. When his master found out and forbade his wife to continue, Douglass sought further tutoring from immigrant boys on the docks where he worked, in exchange for his master’s wife’s fresh-cooked bread. Helen Keller received tutoring from Anne Sullivan. Tutoring has long been known to be effective. The only question is, or should be, how do we maximize tutoring’s effectiveness while minimizing its cost, so that all students who need it can receive it?

If air conditioning had been like education, we might have celebrated its invention, but sadly concluded that it would never be affordable by ordinary people. If penicillin had been like education, it would have remained a scientific curiosity until today, and millions would have died due to the lack of it. If cars had been like education, only the rich would have them.

Air conditioning for all? What a cool idea. Cost-effective tutoring for all who need it? Wouldn’t that be smart?

Photo credit: U.S. Navy photo by Pat Halton [Public domain]

This blog was developed with support from the Laura and John Arnold Foundation. The views expressed here do not necessarily reflect those of the Foundation.