Portfolios are systematic collections of students' work samples over time and may contain materials that focus on particular content areas (i.e., math or[Page 388]language arts), or they may take in materials from across students' school experience (i.e., math and language arts). They serve multiple purposes and are used to highlight students' best work, document their achievements, and evaluate their level of performance. Additionally, they are programmatically implemented at varying levels of educational organization from large-scale programs across states and districts (Kentucky and Vermont), to smaller units such as schools, classrooms, or even particular students.

The use of portfolios in schools provides information that cannot be obtained in norm-referenced, standardized assessments (e.g., standardized achievement tests). In recent years, there has been a trend to use “authentic” assessment ...