Multimedia design principles were applied to an online geography slideshow on geographic information systems (GIS) intended for college students taking an introductory course. In a 2 (segment vs. non-segmented) × 2 (redundant vs. non-redundant) between-subjects design, the base lesson (non-segmented condition) provided a worked example of how to solve an extended GIS problem, consisting of 12 slides with each showing graphics on the left side with corresponding text in the right side. Students progressed through the lesson by pressing the right arrow key to move to the next slide. The segmented lesson (segmented condition) consisted of the same slides, but the material on each slide was presented sequentially in which pressing the right arrow key added a single graphic and/or corresponding text explaining each of 3 or 4 major steps. For both versions, some students received additional narration that was identical to the printed text (redundant condition) or no additional narration (non-redundant condition). On a subsequent transfer test, the results showed a "segmenting effect" in which students performed significantly better with segmented than non-segmented versions of the lesson (d = 0.34), and this pattern was the same whether narration was added or not, yielding no interaction between segmenting and redundancy and no significant effect for redundancy. This work extends the segmenting principle to a new medium, domain, and segment size.