What is the difference between formative and summative assessment?
The distinction is about purpose, not format. The same test can be either depending on what is done with the result.
Formative assessment is assessment for learning. Its purpose is to find out what a learner does and does not understand while there is still time to act on it. Low-stakes quizzes, class questioning, drafts with feedback, exit tickets, homework that is discussed rather than graded. The output is information used to change what happens next — by the teacher, the learner, or both.
Summative assessment is assessment of learning. Its purpose is to measure achievement at the end of a period and record it. Final exams, end-of-unit tests, coursework grades, qualifications. The output is a judgement.
A useful way to remember it: when the cook tastes the soup, that is formative; when the customer tastes the soup, that is summative.
Why the distinction matters:
Feedback only helps if there is a next step. Detailed comments on a final exam that the student never revisits are effort spent on nothing. Feedback on a draft is formative and useful.
Grading changes behaviour. Research consistently finds that attaching a grade to formative work causes students to attend to the grade and largely ignore the comments — an effect found in classic work by Ruth Butler, where comment-only feedback improved subsequent performance while comments-plus-grade did not.
Stakes change what is measured. High-stakes assessment encourages strategic behaviour and anxiety; low-stakes assessment produces a more honest picture of understanding.
The testing effect makes formative quizzing doubly useful — retrieval practice improves retention as well as revealing gaps, so a quiz teaches while it measures.
Ipsative assessment is a third type, comparing a learner against their own previous performance rather than a standard or their peers.