What does standard deviation help a teacher understand about assessment results?

Standard deviation is a statistical measure that indicates how much individual scores in a data set differ from the mean (average) score. When a teacher looks at assessment results, standard deviation provides valuable insights into the distribution of student scores. A smaller standard deviation means that scores are clustered closely around the mean, indicating that most students performed similarly. Conversely, a larger standard deviation signifies a wider spread of scores, suggesting that students had varying levels of understanding or performance.

Understanding the spread of scores is crucial for a teacher because it allows them to identify not only the overall performance level of the class but also how diverse the students' abilities or understanding are within that group. This knowledge can inform instructional strategies, help in differentiating learning materials, or guide interventions for students who may be struggling or excelling.