5 Most Common SLO Growth Target Format Examples: May, 2016

Allowable formats (subject to evaluator approval):

1. Half-the-Gap Formula:

Growth Target = ½ (100 – Pre-Assessment Score)

All students will increase their scores by one half the difference between 100 and the pre-assessment score.

Example: a student who received a rating of 50% on the pre-assessment would be expected to receive a rating of 75% on the post-assessment.

½ (100 – 50) = 25 pts.

Pre-Assessment Score: 50%

Growth Target: 25 pts.

Post-Assessment target score: 75%

2. Half-the-Gap Hybrid Formula:

For use when using the Half-the-Gap formula results in post-assessment score expectations that are significantly less rigorous that would be expected based on historical data with the assessment and/or teacher experience with the content. This is a two-part format.

Example: A pre-assessment for an AP Chemistry course results in no students scoring higher than 24%. The teacher expects most students to score at least 70% on the post-assessment in the Spring. Using half-the-gap formula would result in the expectation that student score no higher than 62%.

1. Students with a pre-assessment score of less than 40% will have a growth target that will result in post-assessment score of 70%

Growth Target = (70 – Pre-Assessment Score)

Ex: Pre-Assessment score of 20% Growth target = (70 – 20) Growth target = 50 points (target score: 20 + 50 = 70%)

2. Students with a Pre-Assessment score of 40% or higher: use half-the-gap formula:

Growth Target = ½(100 – Pre-Assessment Score) Ex: Pre-Assessment score of 44% Growth target = ½ (100 – 44) Growth target = 28 points (target score: 44 + 28 = 72%) 3. District-Set for instrument:

All students with same pre-assessment score will have the same growth target, across the district.

Example: District sets growth targets for kindergarteners using Aimsweb

4. Test-Provided:

Test vendor sets growth targets based on pre-assessment scores

Example: NWEA set Fall to Spring math growth targets for each student in Grade 6

5. PGR:

SLO rating determined by the percentage of the gap reduced between the class’ mean Pre-Assessment score and the maximum score set.

Step 1: Determine Mean Performance Gap (Difference between the maximum score and the class’ mean Pre- Assessment score.)

Example: Mean average Pre-Assessment score for all students in the course: 54 pts.

Step 2: Determine the Mean Performance Growth (Difference between class’ mean Post-Assessment score and the class’ mean Pre-Assessment score)

Example: Mean average Post-Assessment score for all students in the course: 84%

84 – 54 = 30 pt. (mean performance growth)

Step 3: Determine Percent Gap Reduction ((mean performance growth) divided by (mean performance gap) multiplied by 100))

Example: (30 ÷ 46) = 0.65 x 100 = 65% gap reduction (SLO rating – 3.0; see chart below)

PGR SLO Rating Scale:

Mean Gap Reduction Rating 75% or higher 4 50-74.4% 3 25-49.4% 2 25.4% or less 1 *District may want to refine the rating chart using tenths