The purpose of this research was to examine the influence of a confusion-based instructional design in online learning environments on learning outcomes and learners’ confidence. This proposition of instructional design is an implantation of D’Mello and Graesser’s Zone of Optimal Confusion (2012). This model offers a theoretical framework to optimize the learning process by inducing a type of confusion that fosters deeper and more sustainable learning. We recruited university students to follow an e-learning course on First Aid. Participants were tested on knowledge before and after following the course, either in a classic direct instruction or in a confusion-based design. They also reported on emotions and an Error Orientation Questionnaire to determine what factors influence the response a specific design. Despite strong learning gains in both conditions, results showed no significant differences between the two designs. Suggestions for further research are discussed.