We are excited to announce the development and implementation of the interdisciplinary educational module Unknown Bones. Unknown Bones is an inquiry-based activity for high school students in which they apply data analysis and statistics to understand the concept of sexual selection and illustrate sexual dimorphism in Cayo Santiago rhesus macaques. The activity follows the national educational standards. The teacher's guide is available at our webpage to any interested educator. You can download it atthank the staff and students of The School of San Juan for their welcoming enthusiasm and cooperation in implementing this activity. It was a success!