Formative assessment is given to students during instruction, rather than after instruction. For instance, an educator may give tests and homework throughout a unit to gauge a student's progress. Alternatively, she may interact with students in class-wide or individual discussion to determine areas of need or concepts that need to be reiterated. As an another example, a teacher may periodically ask students to write a summary of a lesson or topic in order to assess students' comprehension of the topic before advancing to the next topic. Importantly, formative assessment is ongoing. It is used throughout the learning process to ensure that progress is being made so that students are prepared to advance.
Summative assessment is given to students after, rather than during, instruction. It is used to comprehensively evaluate a student's knowledge and skills after learning has taken place. An example of summative assessment may be a midterm or final exam or a standardized state exam. Summative assessment is a more controversial method of assessment, as many educators maintain that summative assessments do not adequately indicate students' achievements or abilities and that summative assessment cannot inform instruction, since they occur after the fact.
With formative assessment, the educator will use descriptive feedback to show students how they performed well and how they can improve. Formative assessment is distinguished from other kinds of assessment, such as summative assessment, in that the educator provides students detailed commentary. Detailed, descriptive feedback enables students to understand their needs for improvement and resources and suggestions for improvement. Importantly, formative assessment establishes strong communication between students and teacher throughout the learning process.
Generally, summative assessments provide students with a raw score or grade based on their performance on the specific exam. Unlike formative assessment, there is little descriptive feedback provided, since there will be no more instruction or practice during which students have the opportunity to apply feedback. If descriptive analysis of exams is gathered, it is normally used to inform future instruction. Summative assessments, thus, are useful in providing educators with an assessment of the effectiveness of instruction.