Something New: Student Growth Percentiles

Recently the Massachusetts Department of Elementary and Secondary Education released a new set of data to all of the Commonwealth's districts and schools. This data, known as Student Growth Percentiles (SGP), serve to quantify how much each student has grown each year as measured by his/her performance on the MCAS (Massachusetts Comprehensive Assessment System) test each spring. One could simply look at a student's performance and score from year to year, but that wouldn't necessarily be a valid judgment, as the relative difficulty of each grade's tests and accompanying cut scores have some variability. Thus, some scale that could judge a student's performance relative to his/her peers is needed. That's exactly what the DOE has created.

It works this way: Say a student scored 240 (Proficient) in the fifth grade on math MCAS test. He takes the math MCAS in the sixth grade, and that performance is compared to all of his peers in the same grade who also scored 240 in the fifth grade. He scores a 242 as a sixth grader (also Proficient), but his SGP is 70, which means he scored in the 70th percentile of his peers (he scored the same/better than 70% of his peers, and 30% of his peers did better than him). Thus, the SGP is a statistical feature that quantifies growth on a 1-100 scale, comparing each student to his/her peers based upon how they did in the previous year.

This is another nice piece of the data collection that schools now possess to ascertain how well students are learning. The DOE has also released median SGP values for individual districts and schools for the MCAS tests in ELA and math in grades 4-8 and 10. Typical growth has a SGP value of 40-60 while high growth is 70 or higher. These values could show that a school with high proficiency rates (achieiving AYP, or adequately yearly progress) is not growing, a low-performing school is showing growth, or something in between. When the DOE announced the new SGP data, they highlighted the schools that showed significant growth from 2008 to 2009. Many of these schools are in urban settings.

For more information on SGP data, click here. For the Mansfield SGP data, click here. If you will note, the median SGP for the Mansfield High School grade 10 ELA is 60 and grade 10 math is 63. These percentiles show the growth that last year's sophomores (the class of 2011) have made since they took the test as 8th graders in 2007. As a school community, we are pleased that we have demonstrated some growth while maintaining high proficiency rates (94% in ELA, 89% in math, and 86% in science).

SGP data for individual students has been released to schools but not to parents. Parent reports will include SGP data starting with the spring 2010 administration.