The National Center for Research, Evaluation, Standards, and Student Testing (1996) defines criteria as "guidelines, rules, characteristics, or dimensions that are used to judge the quality of student performance. Criteria indicate what we value in student responses, products, or performances."
In alternative assessments, students must clearly understand what criteria will be used to judge their performance. The problem of interpretation differences that result when performance requirements are ambiguous is compounded when students have diverse experiences based on their ethnicity, primary language, or gender. In an effort to assess higher-order cognitive skills and complex problem solving, educators must develop appropriate assessments that have no single right answer and in which students' interpretation of information or evidence is key in defending their solution.
Although student interpretations are important, educators must recognize that on the basis of cultural and environmental norms, explanations that seem diametrically opposed may be equally defensible or right. Because this quality of complexity allows performance assessments to mirror real life, educators must explicitly include the exact parameters of the responses they want to elicit in each assessment task or problem. (For example, educators should make sure students know if the writing process--rather than punctuation and grammar--is the criterion on which performance will be judged, or if a paragraph--as opposed to a few words--is the criterion response.)