Pilot testing in a large geology course shows that a new sentence-headline design of presentation slides was more effective than the traditional phrase-headline design at teaching science to undergraduates. Rather than having a phrase headline supported by a bullet list, the new design relies on a succinct sentence headline supported by visual evidence. In the new design, bullets are not used. The testing of the new slide design involved comparing test scores between a prior section that viewed the traditional design and the test scores of a current section that viewed the new design. On 7 of the 20 questions, the section viewing the new design achieved improvements in test scores that were statistically significant at the 99.9% confidence level. On no question did the prior section viewing the traditional design achieve a higher test score that was statistically significant. The mean test scores on the 20 questions were 71% correct for the earlier group (traditional design) and 82% correct for the latter group (new design). In addition to analyzing the test scores, we conducted surveys that indicate the students preferred the new design over the traditional design by a more than 7-to-1 ratio. These test scores and survey results have implications in the way that presentation slides should be designed not only for science and engineering classrooms, but also for forums of scientific and engineering research.