To cultivate effective reading, all teaching practices must develop higher-order processing, which involves enhancing reading comprehension and its components of vocabulary, grammar, and text structure. This quasi-experimental research aimed at implementing problem-based learning (PBL) with hard scaffolds in a general English course in the Iranian EFL context to investigate its impact on the participants’ reading comprehension. Two intact groups of elementary students, one as the experimental group (N = 40) and one as the control group (N =40) whose homogeneity in language proficiency was checked through the Key English Test (KET) were selected. The experimental group underwent the PBL method with hard scaffolds and the control group received a mainstream reading instruction method. The two groups completed pre-and posttests of reading comprehension. The results of the study, based on multivariate analysis of covariance, indicated that the PBL group with hard scaffolds outperformed the control group in reading comprehension, including its components of vocabulary, grammar, and text structure. The results of the study suggest that practitioners could pay special attention to the PBL method in EFL educational contexts to enhance students’ higher order processing, vocabulary and grammar learning, and text structure knowledge. تفاصيل المقالة