Saturday, June 26, 2021

New study of universal preschool has confusing results...

I've been thinking a lot this past week about reading, vocabulary, and poverty, but I haven't gotten my thoughts in order. In the meantime, I want to note an interesting recent study of universal preschool that raises some interesting questions about what school is good for. The pandemic has taught me that school is important in all sorts of ways, and this study goes along with that lesson.

Preschool leads to more schooling, but test scores don't go up

The new paper, which came out last month, is about the long-term effects of a universal preschool program in Boston. The study finds that preschool enrollment significant boosts high-school graduation, SAT-taking, college attendance, and reduces juvenile incarceration. Interestingly, the study finds that preschool enrollment does NOT have a detectable impact on state achievement test scores. This is an interesting paradox: universal preschool keeps kids in school longer and gets kids to college, but it does not measurably increase their test scores. How could this be?

This finding--that increased attachment to school does not have a detectable impact on test scores--is extremely counterintuitive. School is supposed to make you better at reading and math, and if preschool makes you more likely to stay in school, more likely to go to college, more likely to take the SATs, more likely to stay out of trouble, those behaviors should lead you also to get more of schools benefits, and you should do better on reading and math tests. That this apparent increase in attachment to school does not lead to higher scores seems to suggest, disturbingly, that school itself does not necessarily lead to higher scores. This uncomfortable suggestion reminds me a paper from a couple of years ago about the "summer slide."

The summer slide is famous, but it might not really exist

The "summer slide" refers to the idea that students--especially less privileged students--not only fail to make academic progress over the summer, but actually slide backward. This idea has long been accepted as an established truth. Malcolm Gladwell's book, Outliers, states the idea this way:

"America doesn't have a school problem. It has a summer vacation problem." (Outliers, 260)

The idea is that the gap between rich kids and poor kids narrows during the school year, and then widens during the summer. According to a 2019 paper (von Hippel and Hamrock), this isn't actually true: 

"If summer learning gaps are present, most of them are small and hard to discern."

The 2019 paper is an interesting reminder of how much measurement matters. Learning gaps were thought to widen over the summer not only because testing regimes used different tests for different grades, and scores on the different tests were hard to compare, but also because how you measure the gap affects how much a gap changes. Scaling test results in different ways results in dramatically different accounts of how much a gap widens or narrows:


Ultimately, von Hippel and Hamrock's paper suggests that "reading and math gaps grow substantially more in the first five years of life than they do in the nine years after school begins." 

If the gap is established in early childhood, shouldn't preschool help?

Von Hippel and Hamrock's 2019 paper concludes with a call for investment in early childhood: 

"The growing interest in early-childhood programs—such as preschool, home visits, and new-parent training—is justified. It is vital to invest in early-childhood programs, and it is just as vital to understand why some early-childhood programs succeed in shrinking gaps, whereas others fail to realize their potential."

This makes sense. But, to come back to the paper about preschool, if preschool can help, why didn't universal preschool in Boston raise test scores?

What is the point of school, after all?

Right now, we don't know why the test scores didn't go up. But one deep question this study raises is: What is the point of school?, is the purpose of school to raise test scores, or is it to help students attain other skills or qualities (persistence? obedience? cooperation? organization?). Is it maybe okay that test scores didn't go up? I don't really like that idea, since I think academic skills are fun and useful, but I am open to the idea that school has different kinds of benefits as well, and maybe those are more important.

No comments:

Post a Comment