Study: Older Kindergartners Go On to Achieve More AP Test and College Success
Cross-posted from Inside School Research
Children who are among the oldest in their kindergarten class are more likely than younger classmates to take and pass Advanced Placement exams in high school and to earn bachelor's degrees within four years, according to a study by researchers at the College Board, the New York City-based non-profit that administers the SAT and Advanced Placement exams.
The study, published online in July, will appear in a forthcoming issue of the peer-refereed Journal of Policy Analysis and Management. It is especially relevant, given the "graying" or aging of kindergarten that has occurred as a result of state policies mandating minimum kindergarten entry ages, and parental "redshirting," the practice of intentionally delaying kindergarten entry so that a particular child will be among the oldest in her class.
This most recent study does not focus on redshirting, which could, in theory, result in children being two or more years older than their classmates. However, it does have implications for debates surrounding the age at which children should begin school.
For their analyses, Michael Hurwitz, Jonathan Smith and Jessica Howell zeroed in on children in the same kindergarten cohort who were up to 364 days apart in age because their birthdays happened to fall at different times of the year. In doing so, they tracked 1.6 million students who entered kindergarten between 1991 and 1995 and took the SAT between 2004 and 2008.
The researchers found that older and younger students in the same grade cohort attained similar SAT scores once they reached high school. They were also equally likely to take the SAT, which, in most states, is an optional exam.
Yet, net of demographic influences like socio-economic status and race, students who were among the oldest in their cohorts were 4 to 5 percentage points more likely to take Advanced Placement exams (also optional) prior to high school graduation. They also passed more exams.
"Such differences in AP test taking rates by relative age are particularly concerning in light of the miniscule differences in SAT scores between students with the oldest relative ages and those with the youngest relative ages, which suggest no real differences in academic preparation between these two sets of students," the researchers wrote.
The age-related differences continued even after the students graduated from high school.
Students with the earliest birthdays in their cohorts were 2.5 to 3 percentage points less likely to enroll in two-year colleges. They enrolled in four-year colleges at similar rates but were 2 to 2.5 percentage points more likely to earn a bachelor's degree within four years of high school graduation.
The news is not all bad for students who are young for their grades. Within six years of graduation, younger members of each cohort had caught up with older peers, earning bachelor's degrees at similar rates, the College Board researchers found. And other studies summarized in the Journal of Policy Analysis and Management article found that students who were young for their grades completed college at similar rates, and even earned better test scores. However, overall, past studies have found "largely positive effects of being the relatively older student," the College Board researchers write.
So what to do? After running through several sweeping and potentially costly solutions (year-round schooling, "gap years" between high school completion and college entry), the College Board researchers suggest that educators and researchers begin by first addressing and studying the strong yet puzzling relationship between advanced course-taking and age, a relationship that holds despite the fact that older and younger students appear to be equally well-prepared, as measured by their SAT results.
"If disparities in these longer-term outcomes, like four-year graduation rates, can be corrected through parity in course-taking behavior at the high school level, much more expensive approaches like delayed progression through the educational pipeline may be unnecessary," they conclude.