Student attainment of all-important course goals is not easily measured by paper-and-pencil tests. Whereas portfolio assessment forces alternative ways of thinking by the teacher about what is done and what is measured. Portfolios also provide an important intersection of instruction and assessment. Examining a collection of portfolios can be useful in evaluating the curriculum and instruction within a classroom, a school district, or an entire state. This article describes how a group of high school physics teachers developed portfolios to provide evidence that students have met their course goals, and includes suggestions for incorporating this form of assessment into your curriculum.