Expanded captions are designed to enhance the educational value by linking unfamiliar words to one of three types of information: vocabulary definitions, labeled illustrations, or concept maps. This study investigated the effects of expanded captions versus standard captions on the comprehension of educational video materials on DVD by secondary students who are deaf or hard of hearing. Participants were assigned randomly to two groups, with each group experiencing both conditions in counterbalanced order. Scores from pretests and posttests of vocabulary and informational content revealed no statistically significant differences between the two conditions. The findings are discussed in light of student preferences for expanded captions and screen-capture data that revealed low access levels for the expanded material.