Assessment, broadly defined, means information gathering. Grading (or evaluating) students is certainly one type of assessment. Tests, portfolios, and lab practicals are all assessment devices. However, teachers assess students in other ways. When teachers check for understanding, to determine whether or not to continue teaching about a particular idea and where to go next with instruction, they are also assessing their students. Ungraded pretests and self-tests likewise represent assessment. Any information that helps the teacher make instructional decisions is assessment. This chapter describes various forms of assessment.