The University Network

High School GPA, Not ACT Score, Is A Strong Predictor Of College Graduation

A high ACT score will get you into college, but it won’t guarantee that you’ll make it out with a degree. A recent study comparing ACT scores, GPAs and graduation rates found that there is no correlation between high ACT scores and college graduation.

High school GPA, on the other hand, was found to be a strong predictor of college completion, forecasting graduation at a rate five times stronger than ACT scores. 

The findings shed new light on the value of GPA in assessing how prepared students are for college. GPAs are sometimes thought to be an unreliable indicator of college readiness due to variance in standards and quality across high schools, whereas college entrance exams like the ACT and SAT are thought to be more neutral and reliable. The new study suggests this perception may not be accurate.

The findings may defy common wisdom, but they are supported by previous research on the relationship between standardized testing, GPA and college readiness. For example, a 2018 study by Matthew Chingos of the Urban Institute came to similar conclusions, finding GPA to be the strongest predictor of college graduation, over both the ACT and the SAT.

The new study was conducted by two researchers from the University of Chicago’s Consortium on School Research: Elaine M. Allensworth, the director of the Consortium, and Kallie Clark, a graduate research assistant at the Consortium and a doctoral candidate at the University of Chicago.

The study looked at 55,084 students who graduated from the Chicago public school system between 2006 and 2009. All students in the study immediately enrolled in a four-year college after graduation. 

The Chicago school district is the third largest in the United States, with nearly 400,000 students. It includes a wide variety of neighborhood, magnet, vocational and selective high schools, with equally variant outcomes. The district contains some of the nation’s best and worst performing schools, making it a strong test case for the study. 

Across all high schools, the researchers found strong evidence that high school GPAs are a strong measuring stick for college readiness. Each incremental increase in GPA is associated with an increase in the odds of graduating college.

In contrast, the relationship between ACT scores and college graduation varied between high schools. In fact, at some schools, there was found to be a negative relationship between high ACT scores and the likelihood of graduating college. On the whole, the researchers concluded that the relationship between ACT scores and college graduation was not significant.

The researchers noted that GPAs and standardized test scores measure different skill sets. Success on the ACT requires specific skills like time management and a knowledge of test-taking strategies. GPA, on the other hand, measures long-term performance in a variety of subjects.

The multitude of factors that go into grades, and the ability to measure more abstract skills like work ethic and engagement, may help explain why GPAs predict college graduation more effectively.

“GPAs measure a very wide variety of skills and behaviors that are needed for success in college, where students will encounter widely varying content and expectations,” Allensworth said in a news release. “In contrast, standardized tests measure only a small set of the skills that students need to succeed in college, and students can prepare for these tests in narrow ways that may not translate into better preparation to succeed in college.”

However, GPA is by no means a perfect barometer for college readiness. “Neither [GPA nor ACT scores] capture all the ways in which high schools influence graduation,” the researchers wrote in the study. 

Differences in the quality of high schools maintain a heavy influence on whether or not students graduate college down the road. Students with the same high school GPA or ACT score graduate at different rates, based on the high school they attended. 

In effect, high school GPAs “are not equivalent measures of readiness across high schools, but they are strongly predictive in all schools and the signal they provide is larger than the differences across schools,” the researchers wrote in the study. 

In other words, GPAs are a valuable measure of college preparedness on the intra-school level.

This finding has strong implications for educators. ACT scores are still a significant factor in college admissions, but the study’s findings suggest that there are limits to the long-term value of teaching to the test. Administrators and district officials often use test scores to judge the performance of schools and even teachers, leading many teachers to spend class time on test preparation. But teachers and their students may be better served by focusing on improving in the classroom rather than the exam room.

“Extensive time spent preparing for standardized tests will have much less pay-off for postsecondary success than effort put into coursework, as reflected in students’ grades,” Clark said in the release. “The more that middle and high school educators can support strong engagement in school — helping students overcome barriers to engagement in class, helping them succeed at different types of academic tasks, so that they earn strong grades — the better these educators are supporting academic skills broadly and preparing students for college.”