Toolkit on ocean literacy, released by the Intergovernmental Oceanographic Commission (IOC) of UNESCO, that provides a set of 16 activities that help learners of all ages to deal with sustainable development issues linked to the ocean. The toolkit is the result of a joint work and contributions of members of a global partnership. It provides to educators and learners worldwide the innovative tools, methods, and resources to understand the complex ocean processes and functions and, as well, to alert them on the most urgent ocean issues. It also presents the essential scientific principles and information needed to understand the cause-effect relationship between individual and collective behavior and the impacts that threaten the ocean health.