A formative assessment is a tool for evaluating student learning during teaching in order to gauge whether students are understanding material at the time. It is a learning tool, not a final evaluation of mastery. Formative assessment helps instructors alter their approach to the concepts if students are struggling.
Some types of formative assessment include asking questions during lessons, student self-assessment, reading logs, class discussion, graphic organizers and quizzes. Because it is used to test student learning and adjust teacher methods, it is not usually highly weighed into grades.
Formative assessment is different from summative assessment, which is given at the end of a unit or term to assign grades and determine whether students have learned the material.