means finding out what a pupil understands while there is still time to act.
It is distinguished from assessment, which records a result at the end.
The distinction is about use, not about the .
The same short test is formative if it changes tomorrow's lesson and if it enters a record.
Research on formative practice reports some of the largest effects in education.
Those effects shrink sharply when the practice is implemented as a procedure.
Schools that required three written comments per week produced paperwork and no learning gain.
What works is narrower: a question that reveals a , and a decision made because of the answer.
Marks interfere with this, which is the least finding in the field.
When a and a comment appear together, pupils read the and ignore the comment.
Studies comparing -only, comment-only and both find that comment-only produces the most improvement.
Parents, however, expect marks, and a school that removes them must explain itself repeatedly.
Most by delaying the until the comment has been acted on.
This costs nothing and requires a teacher to hold a class in one place for an extra ten minutes.
Almost every reform that works in education has that shape: small, specific and unrewarding to announce.