Invention activities challenge students to tackle problems that superficially appear unrelated to the course material but illustrate underlying fundamental concepts that are fundamental to material that will be presented. During our invention activities in a first-year biology class, students were presented with problems that are parallel to those that living cells must solve, in weekly sessions over a 13-wk term. We compared students who participated in the invention activities sessions with students who participated in sessions of structured problem solving and with students who did not participate in either activity. When faced with developing a solution to a challenging and unfamiliar biology problem, invention activity students were much quicker to engage with the problem and routinely provided multiple reasonable hypotheses. In contrast the other students were significantly slower in beginning to work on the problem and routinely produced relatively few ideas. We suggest that the invention activities develop a highly valuable skill that operates at the initial stages of problem solving. (Contains 7 figures and 2 tables.)