The Impacts of Problem-Based Learning on Grammar Knowledge of Grade 11 Students at a High School in Vietnam

Abstract

Although grammar is an important part of English learning in Vietnamese upper-secondary schools, grammar instruction is still largely teacher-centered and exam-oriented. This paper reports on the impacts of using Problem-Based Learning (PBL) to teach grammar to Grade 11 students, as well as their perceptions of learning grammar through PBL. A quasi-experimental pre-test–post-test design was used with two intact Grade 11 classes (N = 90) at Nguyen Thuong Hien High School in Ho Chi Minh City. The intervention lasted eight weeks. Quantitative data were collected through 25-item grammar tests administered before and after the intervention and a 12-item perception questionnaire administered to the experimental group. Qualitative data were obtained from semi-structured interviews with eight experimental-group students. The results showed that both groups improved, but the experimental group demonstrated substantially greater gains[cite: 8]. Its post-test mean was 8.705 compared with 7.674 for the control group, and the difference in gain scores was statistically significant, t(88) = −6.169, p < 0.001, with a large effect size (Cohen’s d = 1.30)[cite: 8]. Questionnaire responses were generally positive, with all 12 items receiving high mean ratings (3.75–4.11)[cite: 8]. The interview results further showed perceived benefits in grammar understanding, application, retention, confidence, motivation, and collaboration[cite: 8]. However, students also reported problems related to task difficulty, time management, unequal participation, and the need for teacher explanation and practice[cite: 8]. The findings suggest that PBL can support grammar learning in a Vietnamese English as a Foreign Language (EFL) context when combined with appropriate teacher support and practice[cite: 8].