Kindergarten is in the news. Specifically, teachers, parents, and school administrators are discussing how much time kids should spend in kindergarten just playing. This story tells how some schools are re-introducing water and sand tables into their classrooms. And this story describes some research about whether kindergarten is too early to teach formal skills in reading or math.
There are three studies described in this article--all quasi-experimental. Interestingly, there are three different patterns of results, but all are used to support the argument that kindergarteners should play more. Let's present each one in turn.
Here's the first study:
A 2009 study by Sebastian P. Suggate, an education researcher at Alanus University in Germany, looked at about 400,000 15-year-olds in more than 50 countries and found that early school entry provided no advantage.
a) What seem to be the key independent and dependent variables in this study? What makes this one quasi-experimental, and which design would it likely be?
b) Could you sketch a graph of this result?
c) This study shows a null result. In Chapter 11, you learned how to interrogate a null result to decide if it's a problem of a weak manipulation, insensitive measures, and so on. Apply the tools from Table 11.2 to decide if this study really does support a null effect.
Here's the second study:
Advocates say that starting formal education earlier will help close [acheivement] gaps. But these moves, while well intentioned, are misguided. Several countries, including Finland and Estonia, don’t start compulsory education until the age of 7. In the most recent comparison of national educational levels, the Program for International Student Assessment, both countries ranked significantly higher than the United States on math, science and reading.
d) What seem to be the key independent and dependent variables in this study? What makes this one quasi-experimental, and which design would it likely be?
e) Could you sketch a graph of this result?
f) Can this second study support the claim that "starting school entry later causes kids to score higher on math, science, and reading?
And here is the third study:
Other research has found that early didactic instruction might actually worsen academic performance. Rebecca A. Marcon, a psychology professor at the University of North Florida, studied 343 children who had attended a preschool class that was “academically oriented,” or one that encouraged “child initiated” learning. She looked at the students’ performance several years later, in third and fourth grade, and found that by the end of the fourth grade those who had received more didactic instruction earned significantly lower grades than those who had been allowed more opportunities to learn through play.
g) What seem to be the key independent and dependent variables in this study? What makes this one quasi-experimental, and which design would it likely be?
h) Could you sketch a graph of this result?
i) Can this second study support the claim that "receiving didactic instruction causes kids to get lower grades in fourth grade?"
Suggested/selected answers:
a) This sparse description makes it difficult to determine, but the variables seem to be "early school entry or not" (as the IV) and "academic performance" (as the DV). This study is apparently a non-equivalent control groups post-test only design.
b) A graph of this result might look like this (data are fabricated for the purpose of illustration):
c) You might conclude that with 400,000 kids, there's plenty of power in this study to find an effect of early school entry. So apparently, there is no covariance between the variables of "early school entry" and "school success at age 15."
d) The IV could be stated as "country" (levels being Finland, Estonia, and U.S.) or the IV could be stated as "age at compulsory education" (levels being age 7 or age 5). The DV would be math, science, and reading scores on the Program for International Student Assessment (PISA) This study is apparently a non-equivalent control groups post-test only design.
e) Here's one possible graph (Data are fabricated for purpose of illustration):
f) No; although the covariance is in the appropriate direction and although temporal precedence is established (Because the age of starting school comes before grades on the PISA), there is no internal validity. As a non-equivalent control groups post-test only design, this study has selection effects, because as the article points out, Estonia and Finland "are smaller, less unequal and less diverse than the United States."
g) The IV is type of preschool learning, (levels were "didactic" vs. "child initiated"). The DV would be grades in 4th grade. This study is also a non-equivalent control groups post-test only design.
h) A graph of this result might look like this (data are fabricated for the purpose of illustration):
i) Once again, we have covariance and temporal precedence here (kids in child initiated instruction did better, and the type of instruction came before the 4th grade grades). However, the study does not mention that students were randomly assigned to the two types of instruction, so we have no internal validity. There is a likely selection effect.
