A total of 114 elementary students (57 second graders and 57 third graders) participated in the present study. Treatment group received think aloud practices using textbook topics 20 minutes a week for 9 weeks as part of regular reading classes. Think aloud practice was carried out on the basis of 'Revised Direct Instruction(Explaining, Modeling, Guiding, Practice, and Reflection).' On the other hand, control group received normal reading instruction. The results indicated that treatment group had significantly higher scores in recall test than control group. There was also interaction effect found between grade and group variables. No significant difference was observed in probe questions. This article examined 8 students' think aloud protocols both at the beginning and at the end of activities, and the results pointed out that level of thinking was changed. At the beginning stage, lower level responses (e.g., no response and simple schema activation response) were more frequently observed than higher level responses; while at the end of stages higher level responses (e.g., interpretive response and applicative response) increased. 【key words】 think aloud, reading comprehension, recall test, probe question, level of thinking, revised direct instruction