Performance Criteria Performance criteria are needed to assess the individual pieces that make up a portfolio. Without such criteria, assessment cannot be consistent within and across portfolios.The nature and process of identifying performance criteria for portfolios are the same as that for checklists, rating scales, and rubrics. If the students' portfolios are required for all teachers in a grade or if portfolios are to be passed on to the student's next teacher, it is advisable for all teachers who will use information provided by the portfolio to cooperate in formulating performance criteria. It can also be valuable to allow the students to help identify performance criteria used in assessing the contents of a portfolio because this can give the students a sense of ownership over their performance and help them think through the nature of the portfolio pieces they will produce. Beginning a lesson with a discussion of what makes a good book report, oral reading, science lab, or sonnet is a useful way to get the students think about the characteristics of the process or product they will have to develop.
Setting In addition to a clear purpose and well-developed performance criteria, portfolio assessments must take into account the setting in which the students' performance will be gathered. While many portfolio pieces can be gathered by the teacher in the classroom, other pieces cannot. When portfolios include oral speaking, science experiments, artistic productions, and psychomotor activities, special equipment or arrangements may be needed to properly collect the desired student performance. Many teachers underestimate the time it takes to collect the processes and products that make up portfolios and the management and record keeping needed to maintain them. An important dimension of using portfolios is the logistics of collecting and maintaining the students' portfolios. Portfolios require space. They have to be stored in a safe but accessible place. A system has to be established for the students to add or subtract pieces of their portfolios. Maintaining portfolios requires time and organization. Materials such as envelopes, crates, tape recorders, and the like will be needed for assembling and storing the students' portfolios.
Scoring Scoring portfolios can be a time-consuming task. Not only does each individual portfolio piece have to be assessed, but the summarized pieces must also be assessed to provide an overall portfolio performance. Consider the difference in managing and scoring portfolios that contain varied processes or products compared with portfolios that contain examples of a single process or product. The m ulti focused portfolio provides a wide range of student performance, but at a substantial logistical and scoring cost to the teacher. The single-focus portfolio does not provide the breadth of varied student performances of the multi-focused portfolio but can be managed and scored considerably more quickly.
UNIT IV: ASSESSMENT STRATEGIES FOR SCIENCE
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