We do not set growth targets for districts participating in the Teacher Incentive Allotment (TIA). However, we support districts by embedding their selected growth target into our Pre- and Post-Test reports. If a district chooses to use one of the commonly accepted models to calculate student growth, we can include those calculations in their reports for clarity and planning. Below is a breakdown of the three most commonly used models for setting student growth targets, along with helpful resources from the Texas Education Agency (TEA).
1. Graduated Percent Increase Model
This model uses the student’s pre-test score to determine how much growth is expected. Students with lower pre-test scores are expected to show more growth than those with higher pre-test scores.
Based on the quintile that a student's test score falls into, growth is projected. The lower quintiles expect to grow at a higher rate.
Pre-Assessment Scores | 0-20% | 21-40% | 41-60% | 61-80% | 81% |
Minimum Percent Increases | 25% | 20% | 15% | 10% | Maintain |
Student growth is calculated using raw score improvement from the pre-test to the post-test.
2. Common Percent Growth Model
In this model, all students are expected to grow by a specific percentage. This percent is applied to the difference between their pre-test score and the total possible score.
Example:
Let’s say students are expected to grow by 40% over the year.
A student scores an 18 on the pretest. To calculate 40% growth, you would subtract 18 from 100 (total score available) = 82
Then, you take 82 x 40% (the expected growth) and add back the original 18. 82 x 0.40 + 18 = 51
So, you would target a student moving from an 18 to a 51 by the end of instruction to meet a goal of 40% growth.
The Common Percent Growth Model allows districts to apply one consistent growth rate for all students.
3. Half the Gap Model
This is really the same as the Common Percent Growth Model with a growth target of 50%. It defines the growth target as the halfway point between the pretest score and a perfect score.
Example:
A student scores 40 on the pre-test.
The gap to a perfect score (100) is 60.
Half the gap is 30.
Target post-test score = 70