This is a course on how ecological systems change through time and how to forecast how they will change in the future. It combines reading and discussing primary scientific literature with R tutorials on how to work with time-series data and make forecasts in R. It is taught each Fall at the University of Florida by Drs. Morgan Ernest and Ethan White. The full course including lecture notes and R tutorials is openly available on this site so that anyone can learn these important approaches and skills for themselves. Course materials are openly licensed and developed on GitHub. Anyone is welcome to use the material in their own courses and contributions are always welcome.