The 2024 8th Grade Math STAAR continued both statewide online testing and several new item types. Using a modified version of the statewide item analysis report, I examined the readiness standards that had less than 60% mastery. Each standard has both an analysis of the items themselves to infer what made them so difficult and instructional implications for educators to ensure a more successful 2025 STAAR test.
Standard | # of items | % mastery |
8.7B | 2 | 32 |
8.3C | 2 | 37.5 |
8.10C | 2 | 42 |
8.12D | 2 | 42.5 |
8.4C | 2 | 44.5 |
8.5D | 2 | 46.5 |
8.5I | 2 | 52.5 |
8.4B | 2 | 53 |
8.8C | 2 | 53.5 |
8.7A | 2 | 55 |
8.5G | 2 | 57 |
Access the slide deck here.
8.7B - 32% overall mastery
use previous knowledge of surface area to make connections to the formulas for lateral and total surface area and determine solutions for problems involving rectangular prisms, triangular prisms, and cylinders
#8 - 40% correct
#25 - 24% correct
Analysis
Both problems asked for total surface area (rather than lateral surface area)
Surface area of a triangular prism can be tricky
For #25, numbers used for calculation were fairly simple but text entry added rigor
Instructional Implications
Some students find the total surface area formula confusing (A = Ph + 2B), so showing them how to find it by adding the six faces can be an alternative
Have students practice finding total and lateral surface area of shapes to practice discriminating between the two
8.3C - 40.5% overall mastery
use an algebraic representation to explain the effect of a given positive rational scale factor applied to two-dimensional figures on a coordinate plane with the origin as the center of dilation
#10 - 44% full credit; 18% partial credit; 37% no credit
#28 - 28% correct
Analysis
Students struggled more when dilated image was not shown (#28)
Answer distribution on #28 indicative of guessing
Scale factors are not guaranteed to be integers
Instructional Implications
Have students work with and without image of dilated shape
Focus on scale factors that are fractions or decimals
Dilate a shape and then ask for a specific vertex to reinforce the order in which the vertices are named
Watch the full walkthrough of all 40 items on the 2024 8th Grade STAAR below.
8.10C - 42% overall mastery
explain the effect of translations, reflections over the x- or y- axis, and rotations limited to 90°, 180°, 270°, and 360° as applied to two-dimensional shapes on a coordinate plane using an algebraic representation
#20 - 63% correct
#35 - 21% correct
Analysis
Translation rule (#20) much easier to represent than counterclockwise rotation (#35)
#35 was most difficult item on the test, with C (29%) being most chosen answer and correct answer (D) the least chosen answer
Instructional Implications
Rules for reflections and translations are intuitive, students can deduce them
Rules for rotations (both clockwise and counterclockwise) are not intuitive, should be memorized
Rather than memorizing all rotations, help students see that 90° clockwise is the same as 270° counterclockwise
8.12D - 42.5% overall mastery
calculate and compare simple interest and compound interest earnings
#16 - 37% correct
#24 - 48% correct
Analysis
Instructional Implications
Instead of simply finding interest (simple or compound), have students practice finding the difference or sum of two accounts that accrue interest
Help students can a conceptual understanding of the difference between simple and compound interest
Have students calculate simple and compound interest (same rate) over 10 or 20 years to see the difference
8.4C - 44.5% overall mastery
use data from a table or graph to determine the rate of change or slope and y- intercept in mathematical and real-world problems
#15 - 36% correct
#29 - 41% full credit; 24% partial credit; 35% no credit
Analysis
Instructional Implications
Tables (rather than graphs) are typically more challenging because they require calculation
Ask students to turn tables into real-world situations to help them struggle through various ways to note the y-intercept
8.5D - 46.5% overall mastery
use a trend line that approximates the linear relationship between bivariate sets of data to make predictions
#4 - 31% correct
#39 - 62% correct
Analysis
For #4, more students chose B (42%) than the correct answer (C), underestimating the slope
Both items expected students to estimate beyond the graph to some degree
Variation in answer selections were minimal
Instructional Implications
For those that have difficulty visually finding line of best fine, have students select two points on each graph and estimate slope from that
Plot each point suggested as an answer to assist with visual discrimination
8.5I - 52.5% overall mastery
write an equation in the form y = mx + b to model a linear relationship between two quantities using verbal, numerical, tabular, and graphical representations
#5 - 41% full credit; 20% partial credit; 39% no credit
#31 - 54% correct
Analysis
Students had to generate an equation in slope-intercept form given data in a table and a verbal description
Neither slope was an integer
Slope of #31 still had to be calculated even though given as a verbal description
Instructional Implications
Use of formula to calculate slope is essential
Students might need extra practice calculating slope from a verbal description
8.4B - 53% overall mastery
graph proportional relationships, interpreting the unit rate as the slope of the line that models the relationship
#11 - 42% correct
#40 - 64% correct
Analysis
For #11, both numbers given for the unit rate are off the graph
For #11, all answer selections had positive slopes that are fairly similar, removing accuracy of estimates
Students struggled much less with #40 (both given numbers are on the graph)
For #40, very low percentages chose A (5%) and C (7%), not tripped up by horizontal lines
Instructional Implications
For those that struggle, focus on finding unit rate first and then creating a table of values with a few x-values on the graph
8.8C - 53.5% overall mastery
model and solve one-variable equations with variables on both sides of the equal sign that represent mathematical and real-world problems using rational number coefficients and constants
#18 - 48% correct
#38 - 59% correct
Analysis
Instructional Implications
Students that have difficulty with algebra tiles can work on converting them to an abstract equation
Have students substitute solution into original equation to check their work
8.7A - 55% overall mastery
solve problems involving the volume of cylinders, cones, and spheres
#1 - 72% correct
#30 - 38% correct
Analysis
Both problems simply required students to identify correct formula and solve with calculator
One problem had no visual (#30) and proved to be much more difficult
For #30, almost as many students chose A (26% - formula for volume of cylinder) and B (25% - formula for area of circle) as the correct answer (C)
Instructional Implications
Drawing even a rough sketch of a cone can help with identifying the correct formula
Have students practice differentiating between the various formulas and their uses
8.5G - 57% overall mastery
identify functions using sets of ordered pairs, tables, mappings, and graphs
#3 - 49% correct
#21 - 42% full credit; 46% partial credit; 11% no credit
Analysis
Instructional Implications
Introduce students to various graphs (e.g., quadratic, exponential, absolute value) in continuous and discrete data to help them distinguish functions from non-functions
Have students move between graphs, tables, mappings, and ordered pairs to identify functions
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