The vast extent to which quantitative prerequisites vary among post-secondary geoscience programs often presents a challenge for educators and students alike in courses for which math and physics are foundational. This study discusses the design of GEOAppS, a suite of educational numerical models, and its application toward lowering the barrier-to-entry for quantitative concepts in an upper-level post-secondary coastal processes course. GEOAppS is a software package, built in MATLAB®, that provides animated visualizations of course concepts through a graphical user interface. Nineteen students enrolled in the course participated in this study, which used a within-subjects experimental design, in which students alternated between experimental and control treatments, to evaluate the efficacy of GEOAppS at facilitating student understanding of quantitative concepts. GEOAppS was used as the experimental instructional intervention, while complementary, static visualizations (paper handouts) composed the control treatment. For each instructional treatment, students' learning outcomes were evaluated by: (a) a written exercise completed concurrently to the treatment, and (b) a course quiz administered the following week. Results indicate that students' performance on the written exercises was higher when using GEOAppS than with static visualizations; however, no significant difference between the two treatments was present in the delayed testing quiz scores. Additionally, the data suggest the existence of aptitude-treatment interaction, in which lower-performing students benefited more from GEOAppS than high-expertise students. An end of study survey of student perceptions showed that most students perceived greater learning from GEOAppS and preferred using the models to the static visuals.