Narrated animated solution videos were implemented in a clinical study that compared a mastery setting that employed repeated cycles of testing with instructional support to a group that had a single opportunity to experience the materials. The mastery setting students attempted sequential questions sets on a topic, with animated solutions between each set, until mastery was achieved, combining formative assessment with worked examples. Students showed significant improvement from their first to second tries on similar sets of problems, attributable to the feedback and solutions they were given after the first try. These improvements were shown in two topics, superposition and electric potential. The single try group was given one version of the questions and solutions, and while they were not required to watch the solutions to move forward, they chose to. On a post-test including near and far transfer questions, no significant difference was seen between the mastery group and the single try group, but both significantly outperformed a control group that received no instructional support, indicating that students successfully transferred the skills from the solutions to the post-test.