Having an appropriate amount of formative assessments allows students to feel confident in their levels of understanding and preparation for summative assessments.
Assessments and their method of delivery should directly correlate to the expectations outlined. If a student is being evaluated on specific content, that should have been clearly communicated through expectations and the rubrics provided should break down their demonstration of undertstanding and ability to showcase their knowledge clearly.
Feedback is essential in the learning process. Be sure the feedback provided is intentional, has been thought out, is explained in a way that the student sees guidance toward growth or improvement and is relevant to the project/assessment.