What is the Difference between a Formative Assessment and a Summative Assessment?

Formative assessment is an ongoing assessment used to inform instruction. The frequency is not defined, so it might be weekly or quarterly. Also what type of measure is not defined as long as the information is helpful for the teacher in making adjustments to instruction in an ongoing manner. It could be as simple as classroom observations, a fluency test, or full diagnostic assessment like DORA.

Summative assessment is given a pre-determined intervals. It could be anything from a state assessment, benchmark test, or end of unit test. It specifically is testing the knowledge that a student should have mastered at a particular point in time. It is used for accountability.