Mutations is the final lesson in a three lesson series that includes "A Selection Pressure" and "Conflicting Selection Pressures" from Innovative Technology in Science Inquiry, that leads students to make sense of evolution. This lesson is introduced using a fish population and uses a set of questions to elicit student’s background knowledge and then transitions students into gathering data on a population of sheep. Students investigate population growth when a mutation occurs in the population using an interactive simulation to gather data in order to create an explanation of evolution. This lesson is designed to be done individually, however it could be done in groups depending on device availability. The teacher has the ability to set up a class and assign the lesson through a portal on the ITSI website (requires teacher to sign up for the website for free). The teacher guide can be accessed here after sign up.