What does research say about the importance of formative assessments?
In a 1998 Phi Delta Kappan article entitled, "Inside the Black Box: Raising Standards Through Classroom Assessment," authors Paul Black and Dylan Wiliam summarize their review of the research that would help answer the question, "Do improved formative, classroom assessments yield higher student achievement as reflected in summative assessments, and, if so, what kinds of improvements in classroom assessment practice are likely to yield the greatest gains in achievement?" They found several dozen research projects with sufficient scientific rigor and experimental control to permit firm conclusions. After reviewing the research, they asserted that, "There is a body of firm evidence that formative assessment is an essential component of classroom work and that its development can raise standards of achievement. We know of no other way of raising standards for which such a strong prima facie case can be made." They reported effect sizes of one-half to a full standard deviation, and noted that "improved formative assessment helps low achievers more than other students and so reduces the range of achievement while raising achievement overall." Black and Wiliam report that gains of this magnitude, if applied to the most recent results of the Third International Mathematics and Science Study, would have raised a nation in the middle of the pack among the 42 participating countries (where the U.S. is ranked) to the top five. This research reveals that these achievement gains are maximized in contexts where educators increase the accuracy of classroom assessments, provide students with frequent informative feedback (versus infrequent judgmental feedback), and involve students deeply in the classroom assessment, record keeping, and communication processes. In short, these gains are maximized where teachers apply the principles of assessment for learning.
Black and Wiliam conclude their summary of self-assessment by students as follows: "Thus self-assessment by pupils, far from being a luxury, is in fact an essential component of formative assessment. When anyone is trying to learn, feedback about the effort has three elements: redefinition of the desired goal, evidence about present position, and some understanding of a way to close the gap between the two. All three must be understood to some degree by anyone before he or she can take action to improve learning."