A portfolio is a collection of a student's work that is selected and organized by the student to demonstrate learning or skills. Portfolios can be used for formative or summative assessment. There are different types of portfolios including working, documentary, and showcase portfolios. Working portfolios contain daily work and reflections to monitor student progress over time. Documentary portfolios contain a student's best work to assess achievement. Showcase portfolios feature limited samples of a student's best accomplishments. Effective portfolio assessment involves students, teachers, and parents collaboratively evaluating work according to specified criteria.