system are sequential and conjunctive; they present distinct hurdles that a teacher must pass in order to continue. Each decision has the potential to reduce the pool of prospective teachers. This represents an implicit and underexamined theory about professional development that needs further investigation.

Third, one advantage originally associated with performance-based assessment was its potential as an “antidote for differential performance between majority and minority candidates” (Bond, 1998a:28). However, the experiences of the NBPTS suggest otherwise. Differences between African Americans and whites on the NBPTS assessments mirror those seen for multiple-choice exams. Studies have examined these differences in relation to gender, years of teaching, location of teaching assignment, putative quality of the baccalaureate degree-granting institution, support during preparation for the assessment, assessment exercise type, writing load of the assessment task, assessor training, and assessor ethnicity. None of these factors have been found to fully explain the performance differences observed between African American and white teachers on these assessments (Bond, 1998a, Bond 2000; A.Harman, NBPTS, personal communication, 2001). Bond concludes that the differences “may well be traceable to more systematic factors in U.S. society at large” (1998a:254).

Fourth, none of these assessment programs examine the teaching performances of the same individuals across different contexts of teaching. The different schools and communities in which a teacher is licensed to teach offer unique challenges and opportunities, yet a teacher’s performance is typically evaluated only in a single context. The committee contends that licensure systems should incorporate information about a teacher’s ability to work effectively with students in a variety of settings. For instance, student teaching requirements and the assessment data they yield could be structured to assure multiple contexts that include diverse learners. Also, support and professional development may be needed when teachers (whether beginning or experienced) move into new schools and communities.

In closing, the committee believes that articulating the validity issues that these cases suggest is an important challenge for the field. In Chapter 4 the committee presents an evaluation framework for standardized forms of testing. Some of its criteria apply directly to the assessments described here. The criteria for the purposes of assessment, the competencies to be assessed, and others are meaningful and important to judgments about performance-based assessments of teacher competence. However, for other evaluation criteria, their meaning and utility are less immediately clear for these assessment forms. The developmental nature of the systems in which these assessments reside, the varied ways in which candidates demonstrate their knowledge and skills within assessment forms, the balance between the information value of these assessments and the professional development benefits that accrue to examinees and other participants, and other differences raise issues about the validity evidence needed to support them.