A student growth percentile (SGP) is a measure of how much a student’s score on a state assessment has changed over time compared to students with similar prior test scores. It is a common way for educators to share information about students’ progress with parents and other members of the school community. While the calculations behind SGPs can be complex, SGP information is easy to understand because it is provided in percentile terms familiar to most teachers and school leaders.
When using SGP analyses, districts may choose to format their data in either WIDE or LONG formats. However, we recommend that analyses be run operationally with data formatted in LONG, as it is more straightforward to manage the large amounts of data required for these types of analyses. The lower level functions studentGrowthPercentiles and studentGrowthProjections can be used with both formats, but the higher level wrapper functions require the use of LONG formatted data.
The exemplar LONG formatted data set sgptData_LONG is available for download from the Data SGP site. The sgptData_LONG data set is an anonymized, panel data set that includes 8 windows (3 windows annually) of assessments in LONG format for 3 content areas. The sgptData_LONG includes the following variables: VALID_CASE, CONTENT_AREA, YEAR, ID, SCALE_SCORE and GRADE (required if running student growth projections). There are 6 additional demographic/student categorization variables that are used by the summarySGP function.
There are also several specialized versions of the sgptData_LONG file including a version for teachers that contains the teacher-student lookup files sgpData_INSTRUCTOR_NUMBER and sgpData_STUDENT_ID. These specialized versions can be used with the prepareSGP and updateSGP wrapper functions to simplify the source code associated with these types of analyses.
This year, district Star users will be able to see SGPs for all students in grades 4 through 11. SGPs for high school students are available starting with the 2017-18 year.
The new SGPs will provide a more accurate picture of student learning across time, as they will be based on actual scale scores that have been normalized. In addition, the SGPs will be displayed with up to five years of a student’s test history and will include the 2014-15 Badger performance levels. To view the SGPs for all students, please visit the Data SGP site and select a grade from the Timeframe drop-down menu. The SGPs will appear in the upper left corner of the screen. For more details, please visit the How to Use Data SGP article. We will continue to update the article as we learn more about how to best display the SGPs for all students. Thank you for your patience as we work to implement this change. We are excited to be able to offer these improved SGPs for all students. Please let us know if you have any questions or concerns. Thank you, again. —Judy Hung, Director of Data and Research