In math, Algebra 1 is a make-or-break course.
The class is the gateway to high school math, and struggling to complete it can close off those higher-level pathways—and even jeopardize students’ ability to graduate. Still, a substantial proportion of students fail Algebra 1 on their first attempt.
Why is the class so challenging for so many teenagers? The problem may be rooted earlier in foundational gaps that begin earlier in math, encountered in middle school—and even elementary school, according to a new report from TNTP, an organization that consults with schools on teacher training and instruction, and New Classrooms, a nonprofit that designs personalized learning models.
The new study, based on an analysis of the math patterns of about 2,000 students, could provide clues about how to intervene earlier for struggling students.
Math spirals. Content taught in earlier grades lays the foundation for higher-level work later on. Students who had gaps from prior grades did worse in Algebra 1, the researchers found.
But how teachers address those gaps matters, they say.
There were certain skills from prior grades that seemed to unlock success in the course—those that undergirded the concepts that students would learn in Algebra 1. Students who had mastered that specific set of skills were more successful in the course than students who didn’t have them, even if they had a similar level of general math knowledge.
The findings suggest that helping kids who are behind succeed in this class requires “fine-tuned” support, said Adam Maier, a partner at TNTP and a researcher on the report.
States and districts have proposed a host of different solutions to improve Algebra 1 enrollment and pass rates—accelerating all students into the class in 8th grade, requiring all students to wait until 9th grade, and offering a double dose math of periods, among others.
The report signals that instructional choices are just as important as these policy decisions, said Elizabeth Huffaker, an assistant professor of education at the University of Florida, and the author of a recent brief on evidence-based policy approaches to improve Algebra 1 outcomes.
“All of our policies kind of need to be downstream of some really core teaching and learning principles,” she said.
Why key ‘predecessor’ skills might unlock Algebra 1 success
The report’s authors examined the math performance of about 2,000 students who took Algebra 1 during three school years, between 2021-2024. The students all used New Classrooms’ supplemental online learning platform, which includes lessons on Algebra 1 content and key algebra topics from prior grades. (The sample is not nationally representative—students in the group were most commonly in schools with about 80 percent of students receiving free or reduced price lunch and had more Black and Hispanic students than the typical school in the United States.)
Analyzing student attempts on problems, the authors determined what “predecessor” skills were most likely to support new learning of Algebra 1 content. For instance, being able to solve multi-step linear inequalities requires students to first know how to write and graph inequalities—a 6th grade skill—and translate algebraic inequalities from sentence form to numerical representation, a 7th grade skill.
Students who didn’t have much prior math knowledge at all were the least likely to master new Algebra 1 concepts, with a 13% success rate. Students who had most of the math knowledge from previous grades, but lacked most key predecessor skills, fared slightly better, with a 31% success rate on mastering new Algebra 1 concepts.
But students who had most of the math knowledge from previous grades, including the predecessor skills, did the best. They had a 58% success rate on new Algebra 1 content. These skills span a wide range of topics, from estimating square roots, solving multi-step equations, and representing rational numbers. (See the whole list here.)
Using this past student data, the researchers employed statistical modeling to predict how much students would learn in Algebra 1 classes if their teachers prioritized predecessor skills while also teaching Algebra 1 concepts.
This targeted approach, in which each student received individualized support, outperformed scenarios in which teachers either retaught all prior grades’ content or only focused on grade-level skills.
This finding may seem obvious to teachers who regularly see classrooms of two or three dozen students, all at different levels, and try to differentiate to meet all of their needs. And teachers often say that attempting that kind of individualized attention and activity curation is nearly impossible in a whole class setting—in part due to restrictions on time, and in part because they rarely receive such detailed diagnostic information.
“This is not all on the teacher to take all of this information and do this independently,” Maier said. “They need to be working in a system.”
The report can inform districtwide structures, said Maier.
How the predecessor approach could inform Algebra 1 interventions
Math intervention programs, for example, often aren’t set up to provide this kind of targeted, individualized support, the report’s authors write.
“Our sense is, the more that schools and districts begin to demand these types of capacities, the more the market will adjust to these demands,” said Joel Rose, the CEO and co-founder of New Classrooms.
Employing the key predecessors approach could also help schools reap greater rewards from proven policy solutions, said Huffaker.
Her brief identifies research-tested strategies to drive student success in the subject, including tutoring and extended time during the school day, such as putting struggling students in two blocks of math instead of one. Educators in those settings could “really hone in on those key predecessors,” she said.
Identifying and organizing these skills, as the TNTP and New Classrooms report does, is “quite useful,” said Jon Star, a professor of education at Harvard University who studies math learning. (Star was not involved with the report.) “There’s a granularity in this report that we don’t usually see in other studies,” he said.
Even so, he said, he would be interested in further research that explores how even earlier years of students’ math education affect Algebra 1 success.
The vast majority of key predecessors that the report identifies come from 8th grade math. “On one level, there’s kind of an obviousness to that,” he said.
“But what wasn’t as well addressed here, but perhaps could be, was identifying the kind of predecessor skills in grades 5, 6, 7 that best predict performance in Algebra [1],” he said.
More clarity could be helpful because there’s some disagreement in the field, he said. Experts are divided, for example, on the importance of fractions, Star said. Does understanding how to manipulate them unlock special algebra understanding, or is there some other skill that drives the correlation between students who are good with fractions and students who do well in Algebra 1?
Still, Star appreciated how the report reinforces “the interconnected nature of the math curriculum more generally.”
“There’s an incredibly useful coherence to the structure of the math curriculum,” he said, “where topics do relate and follow closely to prior topics.”
