The Effectiveness of Longman TOEFL Preparation on Students’ Listening, Structure, and Reading Proficiency

This study examines the effectiveness of the Longman Complete Course for the TOEFL Test in improving undergraduate students’ listening, structure, and reading proficiency in an Indonesian English as a Foreign Language (EFL) context. Using a quasi-experimental pretest–posttest design, the study involved 81 undergraduate students in two intact TOEFL preparation classes at Universitas Advent Indonesia during the second semester of the 2025–2026 academic year. Both classes received one semester of structured instruction using the textbook. Data were collected through TOEFL Institutional Testing Program (ITP) pretests and posttests and analyzed using paired-samples t-tests. Results showed statistically significant improvements in listening (t(80) = 8.34, p < .001, d = 0.98), structure (t(80) = 9.12, p < .001, d = 1.04), and reading (t(80) = 10.47, p < .001, d = 1.18). Each Cohen’s d value represents the effect size for its respective skill domain. These large effect sizes indicate substantial gains across all three sections. The findings suggest that the textbook’s structured, exercise-based approach may support TOEFL performance through domain-specific practice and test-taking strategies. This study contributes to EFL test-preparation research by providing skill-specific empirical evidence from Indonesian undergraduate learners.