back is “owned” entirely by the teacher, the power of the learner in the classroom is diminished, and the development of active and independent learning is inhibited (Deci and Ryan, 1994; Fernandes and Fontana, 1996; Grolnick and Ryan, 1987).

Because the assessor, in this context typically the classroom teacher, has interactive contact with the learner, many of the construct-irrelevant barriers associated with external standardized assessments (e.g., language barriers, unfamiliar contexts) can potentially be detected and overcome in the context of classroom assessment. However, issues of fairness can still arise in classroom assessment. Sensitive attention by the teacher is paramount to avoid potential sources of bias. In particular, differences between the cultural backgrounds of the teacher and the students can lead to severe difficulties. For example, the kinds of questions a middle-class teacher asks may be quite unlike, in form and function, questions students from a different socioeconomic or cultural group would experience at home, placing those students at a disadvantage (Heath, 1981, 1983).

Apart from the danger of a teacher’s personal bias, possibly unconscious, against any particular individual or group, there is also the danger of a teacher’s subscribing to the belief that learning ability or intelligence is fixed. Teachers holding such a belief may make self-confirming assumptions that certain children will never be able to learn, and may misinterpret or ignore assessment evidence to the contrary. However, as emphasized in the above discussion, there is great potential for formative assessment to assist and improve learning, and some studies, such as the ThinkerTools study described in Box 6–3, have shown that students initially classified as less able show the largest learning gains. There is some indication from other studies that the finding of greater gains for less able students may be generalizable, and this is certainly an area to be further explored.³ For now, these initial findings suggest that effective formative assessment practices may help overcome disadvantages endured at earlier stages in education.

Another possible source of bias may arise when students do not understand or accept learning goals. In such a case, responses that should provide the basis for formative assessment may not be meaningful or forthcoming.