Teachers at all levels need to measure how well their students are learning. Traditionally, formal tests and written examinations were the only forms of assessment used to determine students' grades and reflect their knowledge and understanding of the material that was taught. Informal methods of assessment, such as checklists and observation of daily work, have become increasingly popular but have not replaced formal assessment.
Concrete and Measurable Evidence of Learning
Formal assessment provides concrete, measurable and objective evidence of learning. Standardised tests are popular because they have been vetted for reliability. Teachers can use test results to measure student progress over time and also to compare one group of students to another. For example, a teacher might administer a test that measures knowledge and understanding of a topic such as photosynthesis before the subject has been introduced, and then administer the same test at the end of the unit to measure the knowledge gained.
Formal Assessment Helps to Sort Students
Frequent formal assessment gives meaningful feedback to students and their parents; this is especially important for students who are experiencing learning problems. These objective measures of achievement can assist in determining the most appropriate course of study for students and help convince parents to place their child in a recommended program. Results of formal assessment are also useful when determining which students are most deserving of awards and prizes as well as for counselling students about their postsecondary options.
Formal Assessment May Be Stressful
Students frequently find formal assessments stressful. They may suffer from text anxiety to such an extreme that they freeze and momentarily forget everything they learnt; in such cases their test results will not be an accurate reflection of their learning. Test conditions might become so unpleasant for them that it negatively impacts their future learning. Students who cram the night before a test might get a relatively good mark but may not retain the information over time. Some students might resort to cheating in high-stakes situations.
Flawed Test Construction
A badly worded question might lead students to misinterpret the problem and miss the opportunity to demonstrate their knowledge. Teachers might unintentionally allow their personal bias about what they consider important to unfairly determine what part of the material will be included on -- or excluded from -- the test; students who know only a limited amount of material may achieve a high score if the test places a great deal of emphasis on the section they happen to know well. Unfortunately, not all tests are constructed to actually measure what they are intended to measure.