How to Interpret Student Growth Percentiles (SGP) Data
Student Growth Percentiles (SGP) are a way of reporting student progress based on how a student compares to other students who have similar academic histories. These comparisons are weighted to produce an individual student’s percentile rank ranging from 1-99 with higher numbers indicating greater relative performance.
The SGP methodology differs from standard growth models and other methods in that it provides schools/districts with the ability to link teacher/student performance to measurable state achievement targets/goals. This provides a powerful incentive for teachers to improve and for schools/districts to motivate educators by linking measurable goals against teacher/student performance. It is critical that districts fully understand how to interpret SGP data and how to use the tools provided by Michigan in order to maximize their effectiveness.
Educators should consider SGP when making instructional decisions and informing curriculum planning processes for future instruction. However, SGPs should not be viewed as the sole factor in evaluating teacher/student performance or determining classroom accountability. SGPs should be used in conjunction with other metrics, including standardized test scores and classroom performance evaluation, to provide the most accurate picture of a student’s educational experience and progress.
When reviewing SGPs, it is important for teachers to keep in mind the underlying mathematical models and assumptions that drive the calculations. These should be reviewed prior to running any operational analyses. Any errors that come up during SGP analysis typically revert back to the process of data preparation so it is critical to make sure that all of the necessary steps are taken to manage the data correctly before any analyses are run.
To assist in this, Michigan has created several data tools that can be downloaded from the BAA Secure Site and used to view a variety of different reports specific to your district/school. These reports allow you to see how your students performed on the assessments compared to their peers and provide a more detailed look at each student’s performance.
These tools also show how many of your students were “inside the curve” and how many were either above or below the curve. This is useful in identifying areas where more targeted differentiation within your classrooms may be needed to meet the needs of your students.
In addition, the data tools show a clearer picture of how achievement and growth correlate by showing that students with lower achievements tend to have less positive growth, while students with higher achievements tend to have more positive growth. This is helpful in assessing the impact of academic interventions on each student and in evaluating the effectiveness of your instructional practices.
The sgpData exemplar data set is an anonymized, panel dataset of 5 years of annual, vertically scaled, assessment data in WIDE format. This data set models the format required for the lower level SGP functions, studentGrowthPercentiles and studentGrowthProjections. These functions require WIDE formatted data and many of the higher level functions are wrappers for these lower function.
The sgpData_INSTRUCTOR_NUMBER is an optional, supplemental data set that identifies the teacher for each student. This supplementary data is only available for teachers in the state who are using the sgpData function to perform operational analyses.