This interactive module explores the biology of sex determination and development in humans, set against the backdrop of the different sex testing policies implemented throughout sports history.

The Click & Learn uses ongoing debates about the eligibility of certain female athletes to participate in women's events as an entry point for students to learn the processes involved in human reproductive development. Students apply what they have learned to evaluate the results of different tests that have been used throughout sports history to qualify female athletes to compete.

The accompanying worksheet guides students’ exploration.