Summative assessments evaluate how much a student knows about a topic and/or the skills a student possesses within the context of the academic standard. It is rare that projects, group work, or presentation events meet the high standard of a summative assessment; instead, these opportunities are best suited to learn and practice the material. As the summary of learning, the “grade” should be 100% based on summative assessments.
Formative feedback events (I don’t like using the word, “assessment” when I’m thinking about formative tasks) practice the material and the performance tasks required to be successful on a carefully crafted summative assessment. Formative feedback events provide the opportunity to practice the material and give the teacher the chance to give quality feedback. As the “practice” of the material, under most circumstances, these should not be figured into the final grade.