This collection of articles from Educational Leadership pulls together some of the best pieces on formative assessment and feedback that will help educators understand how to best use the data they have at their fingertips. The authors tell fellow educators about how to use formative assessment to shape the next phase of instruction and how to look for patterns in students' assessments and assignments—the mistakes students frequently make and the signals that tell what individuals need, what groups of kids need, and what the whole class needs.