The purpose of the present study was to investigate the effect of captioned vs. non-captioned instructional videos on the motivation and achievement. To this end, a pre-test and post-test experimental design was used on 109 sophomores from a Turkish state university. Videos with and without captions of the unit in question were prepared by the lecturer of the course "Graphics and Animation in Education." The first group (captioned video group; n = 57) studied the applied dimension of the course with captioned videos but the second group (non-captioned video group; n = 52) studied without captions. Qualitative and quantitative data were collected for study. Quantitative data were collected via academic achievement test and instructional materials motivation survey while qualitative data were collected by means of focus group interviews to substantiate the quantitative data. The findings indicated that, in contrast to the suggestion of the redundancy principle, motivation and achievement scores of students do not vary according to the instructional video type under investigation (captioned vs. non-captioned). Thereby, it was concluded that a moderating effect of the streaming feature of instructional material should be considered to interpret the redundancy effect. However, further research is needed to better reveal this moderating effect.