Data SGP is a collection of aggregated student achievement and learning data collected over time that educators and families use to measure and track student progress. This information is used to help shape classroom practices, evaluate school/district performance and support broader research efforts. It includes individual-level measures like test scores and growth percentiles as well as aggregated measures at the school/district level such as class size, attendance rates and graduation rates.
Unlike standardized test scores, which are reported by a single administration, SGPs are calculated and reported over multiple years of a student’s academic career. This allows schools and districts to identify trends in student learning and compare them to the learning of students across the state who started with similar knowledge, skills and abilities.
In this way, SGPs can provide more reliable and meaningful information about student learning than simple test score averages, which are based on just one year of assessment data. SGPs are particularly important for accelerated programs where a small but significant number of students can’t keep pace with their peers. This is because SGPs are aggregated using the median, which is not influenced by the outliers in a program. Moreover, SGPs are based on the median for all teachers in a class, so growth is not affected by the handful of students who do worse than the rest of the school.
SGPs are also useful for evaluating teacher performance because they are based on the average of all teachers’ student growth. This is not the same as the value-added measures that are used in our federal accountability system, but it is another useful measure of a teacher’s effectiveness.
For example, SED calculates each teacher’s mean growth percentile by combining the individual SGPs for all of her students and dividing them by the total number of scores. A teacher’s MGP is an indication of how much better her students performed this year than the average student in the same grade. If a teacher’s MGP is 51, that means her students performed better than the median of students in her grade.
SGPs are available for the 2008-09 through 2014-15 school years, but the Badger Exam was only administered in one year. As a result, SGP reports do not include information about student performance on the WKCE or Forward Exams that were administered in previous years. This presents challenges when comparing the growth of students across different assessments. However, we are working on ways to address these limitations by adding more historical data to the SGP dashboard.