Web‐based learning methods are being used increasingly to teach core curriculum in medical school clerkships, but few studies have compared the effectiveness of online methods with that of live lectures in teaching the same topics to students. Boston University School of Medicine has implemented an online, case‐based, interactive curriculum using videos and text to teach delirium to fourth‐year medical students during their required 1‐month Geriatrics and Home Medical Care clerkship. A control group of 56 students who received a 1‐hour live delirium lecture only was compared with 111 intervention group students who completed the online delirium curriculum only. Evaluation consisted of a short‐answer test with two cases given as a pre‐ and posttest to both groups. The total possible maximum test score was 34 points, and the lowest possible score was −8 points. Mean pre‐ and posttest scores were 10.5 ± 4.0 and 12.7 ± 4.4, respectively, in the intervention group and 9.9 ± 3.5 and 11.2 ± 4.5, respectively, in the control group. The intervention group had statistically significant improvement between the pre‐ and posttest scores (2.21‐point difference; P < .001), as did the control group (1.36‐point difference; P = .03); the difference in test score improvement between the two groups was not statistically significant. An interactive case‐based online curriculum in delirium is as effective as a live lecture in teaching delirium, although neither of these educational methods alone produces robust increases in knowledge.