Formative assessment is assessment used while learning is still in progress. Its purpose is to find out what students understand, what they are missing, and what should happen next.
Common examples
Examples include exit tickets, practice quizzes, class discussions, rough drafts, quick polls, peer feedback, teacher conferences, and short written reflections. The point is feedback, not just a final score.
How it differs from summative assessment
Summative assessment judges learning at the end of a unit, course, or project. Formative assessment helps shape the learning before that endpoint.
In plain language, formative assessment is the checkup before the final performance.