Student Growth Percentiles (SGPs)

SGP is a measure of how much a student improves his or her NJ ASK score from one year to the next compared to students across the state who had a similar test score history. For a complete overview click here.

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What are Student Growth Percentiles (SGPs)?

As a central tenet of AchieveNJ, educators are never evaluated on a single factor or test score alone, but on multiple measures of both effective practice and student learning. As part of this system, the state has committed to developing measures of student growth as required under the TEACHNJ Act signed into law in August 2012. By using a growth methodology to calculate student outcomes, the Department recognizes that students enter each grade level at varying starting points and with unique challenges and that we should focus on student improvement, rather than simply how many students attain proficiency.

New Jersey measures growth for an individual student by comparing the change in his or her achievement on the state standardized assessment from one year to the student's "academic peers" (all other students in the state who had similar historical test results). This comparative change in achievement is reported on a 1 to 99 scale as detailed below.

  • Albert is a 5th-grade student in New Jersey.
  • His 5th-grade test score is 165, 5 points higher than his 4th-grade score.
  • The 5th-grade scores of his academic peers (5th-grade students across New Jersey with a score history similar to Albert's) range between 110 and 200 this year.
  • Albert's increase from 160 to 165 from 4th to 5th grade represents growth that was the same or better than 70% of his academic peers.
  • Albert's SGP score is 70.

For a complete overview of SGPs click here (Narrative PDF) or here (PowerPoint presentation).
For a timeline showing the development of SGP and mSGP Data in NJ, click here.

What is mSGP and how is it calculated?

Qualifying teachers (of 4th-8th grade Math and Language Arts assessed by the NJ ASK) are assigned the median SGP (mSGP) score of all of that teacher's qualifying students based on student rosters submitted by the district. (see this Course Roster Verification and Submission guidance for more information). For mSGP to apply, a teacher must have at least 20 separate students with SGPs enrolled in the class for at least 70 percent of the time, and must teach at least 60% of the time, prior to the state test. The process for assigning mSGPs is shown in the graphic below:

SGP Example
Which teachers will receive an mSGP rating?

For mSGP to be part of a teacher's evaluation, the teacher must be:

  • Assigned to a 4th-8th-grade Language Arts or Mathematics course for 60% or more of the year prior to the date on which the NJ ASK was administered, and
  • Assigned 20 unique students by the district through the Course Roster Submission.
    • These students must be enrolled for 70% or more of the course duration prior to the administration of the NJ ASK.

The list of specific courses that a teacher may teach and receive an mSGP rating can be found here Contained in this list, however, are all pre-secondary education Language Arts and Math courses, for example, Language Arts (Grade 1). Normally, first grade teachers would not receive an SGP because their students are not taking the state tests. However, in a situation where a school is offering 4th grade students a first grade language arts course, teachers of this course would receive an SGP according to the three factors stated above. The full list of codes for all courses can be found here.

mSGP data are available only for those who teach Language Arts or Mathematics in grades 4–8 because their students typically have baseline and end-of-year test scores. Given that third grade is the first testing year, there is no baseline data to create an SGP for that grade.

2013-14 is the first year when SGP data will count toward evaluation ratings. As more years of data become available, more 4th through 8th grade Language Arts and Mathematics teachers may become eligible to receive mSGPs and annual mSGP values may encompass multiple years of performance:

  • The qualification that a teacher must have at least 20 unique students with SGPs may be achieved over multiple years (i.e. a teacher may have 12 students for one school year and 14 students the following year, thereby allowing for an mSGP value in the second year when the total is at least 20).
  • In the future, if two or three years of data are available, a teacher will be evaluated on the best available score for the teacher — either the teacher's median score from his or her current roster of students or the median of all student scores over the available years.
    • In 2014-15, a teacher's mSGP may represent the median score for 2014-15 alone, or the median of 2013-14 and 2014-15 combined – whichever is most advantageous to the teacher.
    • In 2015-16, the mSGP may represent the median score for 2015-16 alone, or the median score for 2013-14, 2014-15, and 2015-16 combined – whichever is most advantageous to the teacher.
    • Each subsequent year, the most recent of up to three years of data will be used to determine the highest mSGP for a given teacher.
How does my mSGP score factor into my evaluation?

mSGPs are one of several measures used to examine the work of educators under AchieveNJ. In 2013-14, they accounted for 30 percent of a teacher's overall rating. In 2014-15, the Department is proposing to change that weight to 10%. To calculate a teacher's final evaluation rating, mSGPs are converted to a 1.0 - 4.0 score according to the Median Student Growth Percentile Conversion Chart, then weighted and included along with the teacher practice score and SGO score.

Is mSGP information confidential?

Yes. Evaluation data of a particular employee shall be confidential in accordance with the TEACHNJ Act and N.J.S.A. 18A:6-120.d and 121.e. Teacher mSGP data should be handled in the secure manner one would treat, handle, and store any part of a confidential personnel record and should not be released to the public. The Department strongly recommends that districts store mSGP data in each teacher's personnel file or in another secure manner that is easily accessible to the teacher (either electronically or on paper).

How was 2012-13 mSGP data used as a practice exercise for educators?

On February 4, 2014, the Department published a broadcast memo describing secure district access to 2012-13 median Student Growth Percentile (mSGP) data for all qualifying teachers. This data does not have any consequences for this year's evaluation as it describes student growth from last school year. Instead, the information is being provided primarily to help districts and the Department to examine the data quality, consider related professional development opportunities, and prepare for the distribution of the first official mSGP scores (for 2013-14) next year when they will count for 30% of qualifying teachers' evaluations.

District leaders were provided access to a summary of all teacher mSGP scores, as well as individual reports for each teacher indicating his/her 2012-13 mSGP. School principals and supervisors were asked to share these confidential reports with each teacher with the goal of connecting the mSGP to elements of the teacher's practice and to professional learning opportunities. Please view the detailed User Guide for the Teacher mSGP Report for background on the use of growth measures, a detailed explanation of the calculation of mSGP scores and how they convert to evaluation scores, and suggestions for sharing the data and using it to inform professional growth.

How can I use SGP and mSGP data to inform my practice?

Early in 2013, New Jersey's teacher evaluation pilot districts received 2011-12 teacher mSGP data and were able to use it in a variety of ways, as documented in the Final Evaluation Pilot Advisory Committee (EPAC) Report (p. 27-33). Suggestions from this report are summarized in the User Guide referenced above (p. 6-8), along with additional guidance for district and school leaders in using the data.

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