It is now required for teachers to incorporate computational thinking (CT) into their science classes. Our research modifies the existing structure of a science methods course for preservice teachers to include CT via modeling and simulations. In the first study, preservice teachers were introduced to the basics of coding through an Hour of Code tutorial, followed by an exercise where they programmed an animated model of the solar system using Scratch. In the second study, we created a web-based simulation to visualize Newton's second law of motion (F = ma) with a dynamic graph feature. The simulation is a race between two cars with interactive settings that the user can change, such as changing the mass and force of each car. Results from both studies reveal that after completing the exercises, preservice teachers learned the material effectively, felt that CT exercises would be beneficial in K-8 education, and plan to incorporate CT into their future classrooms.