opportunity to learn. Student achievement can be interpreted only in light of the quality of the programs they have experienced.
Another important shift is toward ''authentic assessment." This movement calls for exercises that closely approximate the intended outcomes of science education. Authentic assessment exercises require students to apply scientific knowledge and reasoning to situations similar to those they will encounter in the world outside the classroom, as well as to situations that approximate how scientists do their work.
Another conceptual shift within the educational measurement area that has significant implications for science assessment involves validity. Validity must be concerned not only with the technical quality of educational data, but also with the social and educational consequences of data interpretation.
An important assumption underlying the assessment standards is that states and local districts can develop mechanisms to measure students' achievement as specified in the content standards and to measure the opportunities for learning science as specified in the program and system standards. If the principles in the assessment standards are followed, the information resulting from new modes of assessment applied locally can have common meaning and value in terms of the national standards, despite the use of different assessment procedures and instruments in different locales. This contrasts with the traditional view of educational measurement that allows for comparisons only when they are based on parallel forms of the same test.
Assessments must be consistent with the decisions they are designed to inform.
Assessments are deliberately designed.
Assessments have explicitly stated purposes.
The relationship between the decisions and the data is clear.
Assessment procedures are internally consistent.
The essential characteristic of well-designed assessments is that the processes used to collect and interpret data are consistent with the purpose of the assessment. That match of purpose and process is achieved through thoughtful planning that is available for public review.
ASSESSMENTS ARE DELIBERATELY DESIGNED. Educational data profoundly influence the lives of students, as well as the people and institutions responsible for science education. People who must use the results of assessments to make decisions and take actions, as well as those who are affected by the decisions and actions, deserve assurance that assessments are carefully conceptualized. Evidence of careful conceptualization is found in written plans for assessments that contain
Statements about the purposes that the assessment will serve.
Descriptions of the substance and technical quality of the data to be collected.
Specifications of the number of students or schools from which data will be obtained.