Engage high school students in deep, concept-driven mathematics with this 10-page, black-and-white “Mathematics of Repetition” Groundhog Day investigation. Designed for Grades 9–12, this unique worksheet set uses Groundhog Day as a symbolic entry point to explore cycles, recursion, functions, rates of change, and breakpoints through rigorous algebraic thinking. Rather than focusing on folklore, students analyze repeating patterns and periodic behavior using sequences, recursive rules, explici