Student Growth Percentiles, or SGPs, compare an individual student’s assessment scores against those of his/her academic peers and can provide teachers and administrators with valuable insight on a range of educational issues, such as whether they are making progress toward meeting academic goals, whether their growth is faster or slower than peers and whether or not current scores suggest they will pass end-of-year exams.
SGP analyses can be carried out easily if data preparation is performed properly. Many errors encountered when performing SGP analyses stem from improper preparation, and can often be remedied simply by revising it again. For maximum value from SGP analyses, however, data must be prepared correctly in order to obtain useful results.
The sgpdata package provides four sample data sets designed for use with SGP analyses. The first, known as sgpData, specifies data in WIDE format used by lower level SGP functions like studentGrowthPercentiles and studentGrowthProjections; while two others known as sgpData_LONG and sgptData_LONG provide LONG format used by higher level functions like abcSGP, prepareSGP, and analyzeSGP.
In sgpData, ID provides an unique student identifier. The subsequent 5 columns, SS_2013, SS_2014, SS_2015, SS_2016 and SS_2017 provide grade level and time information of assessments conducted during those years for all assessments performed by that student in those years; finally SCALE_SCORE gives scale score values. A LONG version of this data set called sgptData_LONG contains these variables for use with higher level SGP functions which require such data.
Finally, the sgpData_INSTRUCTOR_NUMBER data set offers an anonymized student-instructor lookup table which can be utilized by the prepareSGP function to produce teacher level aggregates. For instance, an average teacher score for a group of students can be generated by providing a list of teachers who taught those students in a given year; this information is then combined with the sgpData_SCORE data to produce an average teacher score per pupil in that group.
SGPs can be calculated for individuals or groups (like schools, districts or states). Furthermore, they can also be examined content-wise over multiple years for trend analyses. Utilizing trend analyses, it may be possible to pinpoint the year when a student attained proficiency or began performing below par; this information can provide valuable insight into areas requiring professional development or additional support in any content area. Schools and districts can utilize OSPI analyses to create targeted interventions for underperforming students. Each district decides the level of effort they wish to commit towards student growth initiatives; OSPI resources support such endeavors.