Student Growth Percentile (SGP) is a measure that shows how much academic skills have improved between test sections relative to “academic peers.” An SGP serves as a relative measurement of achievement; when combined with scaled scores and achievement levels, an SGP gives a complete picture of student learning.
An SGP is determined by comparing a student’s current posttest score with their previous pretest score from their MCAS assessment history, in the same grade, who all have comparable MCAS assessment history and academic peer groups from similar demographic subgroups (gender, income) as well as educational programs (sheltered English immersion, special education). Quantile regression can then be used to place these current and previous scores onto an analytic normed scale allowing us to establish their percentile rank.
SGP analyses tend to be straightforward and simple to interpret once proper data preparation has taken place. Errors that arise during SGP analyses often trace back to improper preparation issues due to how most of its functionality depends on long formatted data sets; we recommend working with the sgptData_LONG data set if you plan on running anything beyond basic SGP analyses.
How Can I Interpret an SGP? A student’s SGP measures his or her improvement on an MCAS content area exam relative to peers he or she studies with. This percentage can be reported either “similar” (which means more or less improvement), “more than”, or “less than”. An SGP can be understood similarly to scaled scores or achievement levels.
Students who earned high raw scores on previous MCAS test sections are compared with all the students with comparable history on similar subject-matter exams, meaning even students who appear to be performing very well may realize that maintaining their current level is no guarantee of growth; given its relative nature, SGP metric cannot provide a definitive indication.
An SGP can serve a number of functions, from identifying areas where students need extra support to tracking individual student progress over time and comparing students from the same school or district. Teachers and administrators need to look closely at a student’s growth in relation to academic peers as well as state averages to provide meaningful SGP information. Additionally, when employing the SGP metric it is important to take note of its assumptions. For instance, students whose growth lags behind that of their academic peers could indicate that their teacher did not offer enough challenging learning opportunities.