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Lessons learned from the 2025 8th Grade Math STAAR

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 2026 STAAR test.


Standard

# of items

% mastery

8.7B

2

43.5

8.7A

2

46

8.3C

2

51

8.8C

2

51

8.4C

2

52

8.7C

2

53

8.2D

2

53.5

8.10C

2

55

8.5I

2

56

8.5D

2

57.5

Access the slide deck here.


8.7B - 43.5% 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


#9 - 39% correct


#37 - 48% correct


Analysis

  • For #9, students are given the side lengths and the lateral surface area, have to work backwards to find the height

  • Equation editor increased the rigor

  • #37 is straightforward yet less than half answered correctly

Instructional Implications

  • This standard calls for students to discriminate between lateral and total surface area along with using reasoning to calculate the perimeter

  • Students should be comfortable finding individual dimensions (e.g., height) or surface area

8.7A - 46% overall mastery

solve problems involving the volume of cylinders, cones, and spheres


#21 - 60% correct


#35 - 32% correct


Analysis

  • #21 was a straightforward application of the formula for volume of a sphere

  • #35 required students to used reasoning to find a dimension given the volume and another dimension

  • 34% chose C (formula for volume of a cylinder, missing ⅓)

  • 23% chose B (correct formula but chose radius rather than diameter)


Instructional Implications

  • The more challenging problems for this standard give the volume and a dimension, asking students to find another dimension

  • Focus on manipulating formulas to find dimensions in addition to the volume

Watch the full walkthrough of all 40 items on the 2025 8th Grade STAAR below.

8.3C - 51% 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


#17 - 58% correct


#29 - 44% correct


Analysis

  • Both dilations were enlargements

  • Distractors for #17 were all dilations

  • Distractors for #29 were a mix of translations and dilations

  • 33% chose A, which would work if it was a translation

Instructional Implications

  • Review the differences between rigid transformations and dilations

  • Show students how dilations are always given away by clues given in the question stem

8.8C - 51% 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


#10 - 55% correct

#22 - 47% correct


Analysis

  • Both items required solving (not modeling) equations

  • #10 required the use of the distributive property

  • 20% chose B (only distributed 2*x)

  • #22 involved fractional coefficients

  • 25% chose B (subtracted 27 from both sides)

Instructional Implications

  • Practice the distributive property (used extensively in Algebra 1)

  • Ramp up the rigor by including fractional coefficients

8.4C - 52% 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


#5 - 61% correct


#30 - 34% full credit; 18% partial credit; 48% no credit


Analysis

  • #5 was a straightforward graph

  • 22% chose A (wrong slope)

  • #30 was technically a table hidden within a verbal description

  • The y-intercept was negative, had to be reasoned out

Instructional Implications

  • Real-world scenarios are much more challenging than graphs

  • When utilizing verbal descriptions, include negative y-intercepts

8.7C - 53% overall mastery

solve problems involving the volume of rectangular prisms, triangular prisms, rectangular pyramids, and triangular pyramids


#19 - 59% correct


#23 - 34% full credit; 25% partial credit; 40% no credit


Analysis

  • #19 had no visual but clearly marked dimensions

  • 20% chose B (added two given lengths)

  • The given shape (i.e., kite) might have obscured the right triangles within it

  • One triangle asked for a leg while another asked for the hypotenuse

Instructional Implications

  • Embedding right triangles into geometric shapes increases the rigor

  • Recognition of when to use the Pythagorean Theorem is the first challenge

  • Rotate between finding a leg and finding the hypotenuse

  • Neither problem asked for the converse

8.2D - 53.5% overall mastery

order a set of real numbers arising from mathematical and real-world contexts


#4 - 41% correct


#38 - 66% correct


Analysis

  • Both problems involved mathematical rather than real-world contexts

  • Only #4 included negative values

  • 32% chose B, misinterpreting the size of negative values

  • #38 was straightforward with the use of the calculator


Instructional Implications

  • Correctly ordering negative values provides much more of a challenge than positive values

  • Students should use a number line and convert even easy fractions to decimals for correct evaluation

  • Think of absolute value when ordering negative numbers


8.10C - 55% 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


#6 - 67% correct


#32 - 23% full credit; 39% partial credit; 38% no credit


Analysis

  • #6 had visual cues while #32 used verbal descriptions only

  • Reflections across an axis can be derived visually while rotations largely require memorization of rules


Instructional Implications

  • When possible (e.g., reflections), student should sketch a graph to aid in rigid transformations

  • Students should memorize the rules for two rotations (90° clockwise and 90° counterclockwise), knowing that a 270° counterclockwise rotation is the same as a 90° clockwise rotation


8.5I - 56% 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


#16 - 42% full credit; 21% partial credit; 36% no credit


#40 - 59% correct


Analysis

  • #16 required students to use the slope formula to calculate the slope and then plug one of the points into the equation to solve for b

  • Drag and drop increased the choices from 4 to 5

  • #40 gave both the slope and y-intercept in verbal form which simply needed to be interpreted

  • 25% chose C (inverted slope and y-intercept)


Instructional Implications

  • Involving multiple formulas (e.g., #16) increases the opportunities to make mistakes


8.5D - 57.5% overall mastery

determine the circumference and area of circles


#8 - 54% correct


#31 - 61% correct


Analysis

  • Both problems required extrapolation (harder) rather than interpolation (easier)

  • For #8, 30% chose B (underestimated slope)

  • For #31, 21% chose B (overestimated slope)


Instructional Implications

  • Students should always draw a line of best fit that includes half of the points above and half of the points below

  • Plotting all four answer choices greatly reduces the reasonable answer selections



 
 
 

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