Formative assessment is a crucial aspect of teaching and learning in the classroom, but there is evidence that there has been a lack of effective implementation of formative assessment in practice. In response, this article outlines the design and development of a formative assessment framework that can be implemented as a consistent whole-school approach to embedding practice that is owned and developed by teachers. The approach outlined in the framework, therefore, is designed to integrate formative assessment practices within a school system context, providing advice and support to school leaders and teachers. The framework in practice should act to enable teachers and students to develop new understandings and perspectives about each other and the nature of teaching and learning, as well as ways to implement new practices of teaching and learning supported by reflective modes of active participation.