By the Illustrative Mathematics team
A new analysis conducted by Leanlab Education found that schools in Los Angeles Unified School District (LAUSD) using IM® Math demonstrated stronger mathematics growth than similar schools that were not. The gains were equivalent to approximately three to four additional months of learning each year. These schools also improved at more than twice the average statewide rate of mathematics growth.
The findings add to growing evidence that high-quality instructional materials can support stronger student outcomes—especially when paired with sustained, curriculum-aligned implementation support.
In LAUSD, that meant aligning curriculum, professional learning, coaching, leadership, and implementation support around a shared vision for mathematics teaching and learning. The result was a coherent system designed to help educators implement it effectively over time.
For any educator working to improve mathematics outcomes, these findings reinforce an important reality. Adopting high-quality instructional materials is only the beginning. Lasting improvement depends on how well those materials are supported in classrooms and across the broader system.
Key Findings from the Analysis
Using publicly available California assessment data, Leanlab Education conducted a retrospective quasi-experimental analysis examining the relationship between IM Math implementation, curriculum-aligned implementation support, and school-level mathematics achievement. The analysis explored two primary questions:
- Do schools using IM Math demonstrate different growth patterns than similar schools not using IM Math?
- Does curriculum-aligned implementation support appear to influence student outcomes over time?
The findings revealed several consistent patterns:
1. Students in IM Math schools demonstrated faster growth.
Across schools matched by demographics, grade level, and prior achievement, IM Math schools grew at a faster rate in mathematics. The difference amounted to approximately three to four additional months of learning each year.
2. IM Math schools outpaced statewide mathematics growth rates.
Schools implementing IM Math improved at more than twice the average statewide rate of mathematics growth, suggesting that their gains exceeded broader statewide trends.
3. Sustained implementation support was associated with stronger outcomes.
The strongest gains appeared in schools that paired IM Math with curriculum-aligned professional learning and implementation support. Researchers found that schools receiving this support demonstrated stronger growth after implementing IM Math than they had before the support was introduced. The relationship also strengthened over time, suggesting that the benefits of sustained support may compound across multiple years.
Taken together, the analysis’ findings suggest that strong instructional materials and strong implementation efforts work hand in hand. The schools experiencing the strongest outcomes were not simply using a curriculum—they were building systems that supported educators in bringing that curriculum to life.
Why These Findings Matter
Research has consistently shown that high-quality instructional materials can improve student outcomes. Yet curriculum alone does not change classroom practice.
The Leanlab analysis suggests that implementation conditions matter. Between 2022–23 and 2024–25, the difference in outcomes between schools receiving implementation support and those that had not yet received support continued to grow, suggesting that the relationship between support and student outcomes strengthened over time.
The national conversation about mathematics improvement often focuses on which curriculum districts choose. These findings point to an equally important question:
How well are schools supported in implementing that curriculum?
To better understand that question, it helps to look at how LAUSD approached implementation.
The Story Behind the Results
In 2015, with support from LAUSD, the Partnership for Los Angeles Schools adopted IM Math across its network of schools serving students in Boyle Heights, Watts, and South Los Angeles. But rather than treating curriculum adoption as a standalone initiative, the Partnership invested in the conditions needed for successful implementation.
Teachers participated in curriculum-aligned professional learning. School leaders received support in strengthening instructional leadership. Coaches worked alongside educators to build expertise, support classroom implementation, and foster continuous improvement.
Together, LAUSD and the Partnership aligned curriculum, professional learning, coaching, leadership, and implementation structures around a shared vision for mathematics teaching and learning. The findings from the Leanlab analysis suggest that this coherence played an important role in the stronger outcomes observed across participating schools.
Three Takeaways for Districts
While every district’s context is different, the findings from the Leanlab analysis offer several practical considerations.
1. Curriculum Adoption Is a Starting Point, Not a Finish Line
Adopting high-quality instructional materials is an important first step, but it is only the beginning of the work. Teachers and leaders need time, structures, and support to translate instructional materials into consistent classroom practice.
2. Implementation Is a Long-Term Investment
The relationship between support and student outcomes strengthened over multiple years. Districts may benefit most when implementation efforts are sustained rather than treated as short-term initiatives.
3. Coherence Matters
Stronger outcomes are more likely when curriculum, professional learning, coaching, and leadership are aligned around a common instructional vision. When these elements reinforce one another, districts create conditions that support both educators and students.
Conclusion
The experience of LAUSD and the Partnership for Los Angeles Schools offers a compelling example of what long-term instructional improvement can look like in practice.
Leanlab’s analysis adds to a growing body of evidence suggesting that meaningful gains in mathematics achievement are more likely when high-quality instructional materials are paired with sustained support for educators. It also reinforces a belief that has guided Illustrative Mathematics from the beginning: Students are capable of rigorous mathematics when the systems around them are designed to support their success.
The lesson from LAUSD is not simply that curriculum matters. It is that lasting improvement happens when curriculum, professional learning, coaching, and leadership work together toward a common goal. When districts create that kind of coherence, they create the conditions for stronger teaching, stronger learning, and stronger outcomes for students.
Next Steps
The findings from LAUSD suggest looking beyond curriculum adoption alone. Consider how curriculum, professional learning, coaching, leadership, and implementation support in your district work together to create coherence across the system.
Read the full Leanlab Education analysis to explore the findings and learn more about how sustained, curriculum-aligned implementation support can help districts strengthen mathematics teaching and learning over time.
Visit Illustrative Mathematics to see how IM Math and curriculum-aligned implementation support can help your school or district create engaging, rigorous mathematics learning experiences that lead to lasting student success.
Want to learn more? Connect with the Illustrative Mathematics team to discuss your district’s goals, explore implementation support options, or learn more about IM Math. Schedule a call or email us at [email protected].
