How to help students do better in school? Maybe we should try hiring better-looking teachers. Or subsidize gym memberships and makeovers for the teachers we already have.

Those, at least, are the implications of a new study from researchers at the University of Nevada, who designed a simple but revealing experiment using college students to see whether a lecturer’s attractiveness has any impact on how much of the lecture students retain. If you guessed that the answer is yes, go to the head of the class. Extra credit if you intuited that teacher attractiveness had other effects as well.

More surprising: The researchers don’t think that sexual interest explains the results, which held up whether the teacher and students were of the same sex or not. This suggests, they write, that the improved student performance was “driven by processes independent from human sexual attraction, such as attention and motivation.” Or, as one of them put it, it’s just human nature.

Here’s how the experiment worked. The researchers asked 131 college students to listen to a recording of a 20-minute introductory physics lecture. The students were randomly assigned to a male or female lecturer, each of whom read an identical text. While the lecture was playing, a computer displayed what the volunteers were told was a photo of the lecturer—who was highly attractive in some cases and not as fetching in others. (Earlier volunteers had rated some photos of possible “lecturers” for attractiveness, enabling the researchers to pick the best- and worst-looking.) Taking notes was barred.

After the lecture, participants got a 25-item quiz on the material. For those with the attractive instructor, the average score was 18.27; for those with an unattractive one, the average was 16.68. That gap isn’t huge, but it is statistically significant, the researchers said.

After being quizzed on the material, participants were asked to evaluate the lecturers. Sure enough, students found the attractive instructors more motivating, easier to follow and possessed of greater health, intelligence and competence. They also generally agreed about the attractiveness of the lecturers.

Overall, the findings are consistent with a mountain of previous research about the effects of physical attractiveness. Earlier studies have found that good-looking people are considered more capable, intelligent, persuasive and socially skilled.

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