Does Placement in High-Achieving High School Classrooms Improve Long-Term Educational Outcomes?

This study investigates whether placement in high-achieving high school classrooms affects students' long-term educational outcomes. Using data from a large selective Chinese high school, researchers examined test scores and university enrollment outcomes for students assigned to high-achieving versus regular classrooms based on a standardized exam cutoff. The study found that placement in high-achieving classrooms increased math test scores by 23-28% of a standard deviation, with gains persisting over three years. Additionally, these students were 17 percentage points more likely to enroll in elite universities, largely due to improved scores on the national college entrance exam. Teacher quality was a key factor driving these effects​.

Central Research Question

This study explores whether being placed in high-achieving high school classrooms positively influences students' academic performance and long-term educational outcomes. Specifically, it seeks to understand if students in these classrooms achieve higher test scores, especially in mathematics, and are more likely to attend elite universities. The research addresses an important question in education policy regarding tracking or grouping students by achievement level within schools and its long-term impact on students’ educational trajectories.

Previous Literature

Prior research on the effects of tracking or achievement-based classroom placement has shown mixed results, with some studies indicating benefits and others suggesting that it may exacerbate educational inequalities. Studies in the United States and other countries have examined whether grouping high-achieving students together can support their educational success, especially for minority and low-income students. For example, U.S. research on gifted programs and honors courses has shown that these settings can improve academic outcomes, particularly in mathematics and reading, for high-achieving students. However, other research highlights potential downsides, such as widening the achievement gap by concentrating resources and opportunities among already advantaged students. Much of this literature has focused on elementary or middle school settings, leaving a gap in understanding the effects of achievement-based classroom grouping in high schools, particularly in countries like China where this practice is widespread.

Data

The study uses detailed administrative data from Qingyang First High School, a large, selective high school in Gansu, China. Data were collected on three student cohorts (2015-2017) and include information on students’ classroom assignments, high school entrance exam scores, classroom placement exam (CPE) scores, and scores on tests taken throughout high school, as well as their scores on the college entrance exam (Gaokao). This rich dataset allowed the researchers to track both short- and long-term academic outcomes, including university enrollment, providing insight into the cumulative effects of high-achieving classroom placement. The dataset also included information on classroom characteristics such as teacher quality (based on rank, experience, and salary scale), class size, and the average ability level of peers in each classroom. These classroom-level factors allowed the researchers to examine potential mechanisms driving the observed effects.

Methods

To estimate the causal effect of being assigned to a high-achieving classroom, the researchers used a regression discontinuity design (RDD) based on the CPE score cutoff. Students who scored just above the cutoff were assigned to high-achieving classrooms, while those scoring just below were placed in regular classrooms. This design allowed the researchers to compare students with similar abilities but different classroom placements, thus isolating the effect of classroom assignment on academic outcomes. The authors used optimal bandwidth selectors to focus on students close to the cutoff and employed local linear regressions to estimate the effects of high-achieving classroom placement on both short-term outcomes (test scores in various subjects during high school) and long-term outcomes (college entrance exam scores and elite university enrollment). This method minimizes bias by focusing on students whose performance was similar but fell on either side of the CPE threshold.

Findings/Size Effects

The study found substantial benefits associated with high-achieving classroom placement, particularly in mathematics. Key findings include:

1. Academic Performance: Placement in high-achieving classrooms increased math test scores by 23-28% of a standard deviation in the first year, with these effects persisting in subsequent years. However, the effects on Chinese and English language performance were muted, suggesting that the benefits of high-achieving classroom placement were concentrated in math.

2. College Entrance Exam Scores: Students placed in high-achieving classrooms scored 26-28% of a standard deviation higher on the Gaokao, China’s college entrance exam. This increase in exam performance was particularly pronounced in math and science subjects, which are critical for college admission, especially in elite universities.

3. University Enrollment: High-achieving classroom placement increased the likelihood of enrollment in elite universities by 17 percentage points. Elite universities, especially those in Project 211 (top 100 universities) and Project 985 (top 40 universities), offer substantial labor market benefits for graduates, such as higher starting salaries. By raising college entrance exam scores, high-achieving classrooms gave students a competitive edge in the highly selective Chinese college admissions process.

4. Mechanisms: The primary mechanism driving these positive effects appears to be teacher quality. Students in high-achieving classrooms were exposed to higher-ranked and more experienced teachers, who are perceived as higher quality within the Chinese educational system. Smaller class sizes and exposure to high-achieving peers also contributed to the positive outcomes but to a lesser extent than teacher quality.

These results demonstrate that high-achieving classroom placement can have lasting effects on students’ academic trajectories, not only by improving test scores during high school but also by enhancing access to elite higher education institutions.

Conclusion

This study provides robust evidence that high-achieving classroom placement in high school has substantial benefits for students’ academic performance, especially in mathematics, and significantly increases their likelihood of attending elite universities. The findings contribute to the broader debate on tracking and classroom grouping by achievement level, indicating that for high-achieving students, placement in advanced classroom settings can facilitate long-term educational success. While the study focused on a specific high school in China, the results have broader implications for educational policies worldwide, suggesting that grouping high-performing students together, when coupled with high-quality teachers, can improve educational outcomes in competitive settings.

However, the study also highlights that these benefits may not be evenly distributed across subjects, as the effects on language subjects (Chinese and English) were limited. This suggests that similar grouping strategies may need to be adapted to address subject-specific needs. Additionally, the study emphasizes the importance of teacher quality as a mechanism for improving outcomes, underscoring the need for policies that ensure high-quality teachers are available in high-achieving settings.

In summary, high-achieving classrooms appear to offer a pathway for talented students to maximize their academic potential and access opportunities for higher education and career success. This study’s findings support targeted classroom placements as a viable approach to fostering academic achievement among high-performing students, particularly in competitive educational environments where college entrance is determined by rigorous standardized exams. Future research could expand on these findings by examining the effects of high-achieving classroom placement in a broader range of schools and contexts, as well as by investigating how these effects vary across different student demographics and subject areas.

Citation

Canaan, S., Mouganie, P., & Zhang, P. (2024). The long-run educational benefits of high-achieving classrooms. Journal of Policy Analysis and Management, 1–27. https://doi.org/10.1002/pam.22636