Abstract: Computer-Aided Instruction (CAI) can be effectively used in blended learning environment to achieve pedagogical goals. However, CAI systems typically lack of effective feedback mechanisms that ultimately lead to improve learners performance. This study introduces a CAI system equipped with effective dual feedback mechanism. The system provides effective feedback to the learners and maximizes the value of their feedback to instructors. The effect of the system was measured in the field on groups of learners. The results showed that the feedback mechanism of the system has positively impacted the performance of the learners.