In light of the increased usage of instructional media for teaching and learning, the design of these media as aids to convey the content for learning can be crucial for effective learning outcomes. In this vein, the literature has given attention to how concurrent on-screen text can be designed using these media to enhance learning performance. The present study sought to examine whether utilizing concurrent on-screen summarized text (CST) could improve students' learning performance while estimating their perception of performance when learning with educational multimedia content. Although the findings did not show a significant improvement in students' performance on the retention test among the CST groups, students exhibited a considerable higher level of confidence toward their performance. The findings suggest that students who learned with CST educational media may have overestimated their performance. Further analysis and discussion are included.