A recent report published in the Journal of Adolescence has shown that students who chewed sugar-free gum over the course of the school year significantly improved their test scores. The study, conducted by the Baylor College of Medicine, randomly assigned eighth grade students to either a “gum group” or “no-gum-control group”. These students chewed gum during math class and during math homework. By the end of the year, the students in the gum group improved their math scores more than that control group (p=0.03). Although statistically significant, the increase was relatively modest ~ a 4%. This would translate into a third of a grade increase ex. B+ to a A-.
The full study can be read here: Johnston CA, Tyler C, Stansberry SA, Moreno JP, Foreyt JP. Brief report: Gum chewing affects standardized math scores in adolescents. J Adolesc.2011 May 25.