The data sgp package provides an efficient means of organizing longitudinal (time dependent) student assessment data into statistical growth plots. It does this by utilizing two common formats for such data, WIDE and LONG; WIDE format essentially treats each student as one case/row while LONG spreads time dependent variables across multiple rows per student. The SGP package contains a variety of analyses that may be run on both WIDE and LONG formatted data. However, it is recommended that all operational analyses of SGP data be performed using the LONG formatted sgpData. This is due to several preparation and management advantages of the longer data set when compared with the WIDE.
Student Growth Percentiles (SGP) provide an indicator of how a student’s performance on an MCAS test compares to students with similar MCAS score histories. For example, a student who grows at the 90th percentile has an MCAS score that is higher than 90% of students with similar scores on previous tests.
A key feature of SGPs is that they are based on a standard distribution. As a result, for any given grade level and subject area, each decile (grouping of 10 percentiles) is expected to have roughly the same number of students as any other decile. Despite this, there is some variation among schools.
For example, a school that has very few teachers for a particular content area or grade level will likely see some variation in the average student growth within a specific decile. This is because not all teachers have the same number of students. To help mitigate this issue, the SGP package includes a set of tools for analyzing and interpreting student growth. These tools allow educators to identify students who need additional support and help them determine which strategies will be most effective for their classroom.
The SGP database contains many different types of student performance information, including academic achievement, social/emotional skills, and behavioral issues. This data can be used to inform teachers’ instruction and interventions, as well as to monitor student progress over time. The SGP database also allows districts to assess the effectiveness of their programs and services.
Currently, SGPs are available for ELA and math. Students in grades 3 through 8 have SGPs established for their science scores as a combination of their MCAS tests in those grades. Students in grades 9 have SGPs established for their ELA and mathematics test scores compared to their MCAS test scores in their previous grade.
In the future, DESE will begin preparing SGPs for science as well. However, because the Badger Exam and subsequent Forward Exam were administered in a very different timeframe than the WKCE and previous MCAS tests, it is not feasible to establish longitudinal SGPs for science students until a full year of data can be collected.