In American public schools, lower-income students rank about 3 academic years behind their peers. By the time they reach high school, their average literacy skills are 5 years behind well-off peers. Moreover, if current trends persist, most states aren’t going to see any changes in the years to come.
The good news is that assessment leaders looking for ways to close the achievement gap do have resources at their disposal. Open educational resources (OER), that is. By using free textbooks, tutorials, and instructional activities, educators can put peer-reviewed resources in the hands of their learners, even in the face of socioeconomic challenges.
This article will break down how assessment leaders are using OER to try to close equity gaps in education.
The “equity gap” refers to the gap between low-income students and their middle-income and high-income peers. Sadly, while spending on education has grown, this gap has not shrunk. One of the reasons for this is the focus on a skills-based curriculum.
Instead of focusing on knowledge, a skills-based curriculum tries to impart skills like “problem-solving” or “research.” While problem-solving is obviously a part of any good education, students need to acquire knowledge first in order to make sense of the problems they’re trying to solve. For instance, in a country in which only 7% of people can name the rights protected by the First Amendment, it’s unrealistic to expect young students to research, understand, and propose solutions to civic issues.
Skills-based curricula also widen the equity gap. When students come from wealthy, educated backgrounds, they typically possess a great deal of knowledge from their home and social environment. As a result, a focus on skills might be the appropriate next step for their needs. The same isn’t the case for students from poor, uneducated families, however. Without the same foundational knowledge, they’re disadvantaged and unsurprisingly perform worse when assessed on skills—further entrenching the very inequities schools aim to close.
One of the pioneers of the OER movement, the non-profit Core Knowledge, captures the spirit of delivering equity through knowledge-based curricula. They write, “Educational excellence and equity require that every child in a democracy has access to important shared knowledge and language.” Core Knowledge’s free digital curriculum (physical copies are sold for as little as $1.99 for an activity book) specifies and transmits the knowledge that every citizen needs to participate in society.
The effectiveness of this approach is supported by research. When researchers at the University of Virginia set out to measure the impact of knowledge-rich curricula like Core Knowledge, they found that “students’ cumulative, long-term reading test scores increased by approximately 16 percentile points.” The results indicate that if the entire US moved to a knowledge-based curriculum, as opposed to a skills-based curriculum, the nation would place 5th globally on the 4th-grade Progress in International Reading Literacy Study (PIRLS) reading test—instead of 15th.
A 2023 long-term study also looked at the effect that knowledge-based curricula had on the achievement gap. At the low-income school included in the study, improvements in English Language Arts, mathematics, and science were so large that they “eliminated the achievement gap associated with income.”
If you’re an assessment leader looking to close equity gaps, this finding is critically important. It suggests that when educators are equipped with knowledge-based curricula, they can achieve equal outcomes, regardless of the socioeconomic background of their students. And with so many OER providers out there, you have many chances to find the right free, open resources for your classrooms.
Core Knowledge is far from the only organization that creates high-quality, peer-reviewed educational resources at no cost to users. In fact, there are many OER non-profits that put everything from full curricula to one-off activities in the hands of educators and administrators. While each has its specialties and its drawbacks, they’re all united by a commitment to give students the knowledge they need to gain a solid education regardless of their socioeconomic background.
Some of the most well-regarded OERs include:
Every OER provider is different. Some offer only peer-reviewed courses, while others provide an open framework that any educator can contribute to. Moreover, each OER has distinct accessibility standards.
To find the right OER for your institution, start by outlining your organization’s needs. Assessment data can help here. Are students struggling with math, reading, or science? If, as is so often the case, they are behind grade level in all areas, start with the low-hanging fruit. Then, find OERs that place knowledge at the center of instruction.
As might be expected, MIT’s OCW and Hillsdale College Courses are going to be a good fit for advanced high school students who don’t have access to excellent lecturers. If your school has limited AP courses available, some of these courses may be the best way to offer your brightest students access to a challenging curriculum.
If, on the other hand, you’re trying to help young learners catch up on elementary-level skills, you may want to start with something from Core Knowledge, the CK–12 Foundation, or the OER Commons. These organizations specialize in making basic content available to the youngest students.
The potential of OER is clear: it broadens access, cuts costs, and fosters collaboration across classrooms. But the missing link is often assessment. If schools adopt OER but rely on proprietary testing systems, they’re still locked into silos where materials can’t be shared or adapted freely—potentially leading to the siphoning off of funds from other projects.
That’s where open-source assessment platforms come in. For example, TAO is built on open standards such as the IMS Question and Test Interoperability specification (QTI) and Learning Tools Interoperability (LTI), so OER content can be integrated directly into the assessment environment. Educators can design tests, quizzes, or formative checks using the same open materials they teach with—maintaining continuity between instruction and evaluation. This interoperability ensures that assessments aren’t just an afterthought but a seamless extension of OER-driven learning.
Pairing OER with an open-source platform also empowers schools to customize assessments to align with their curriculum, share resources across districts, and future-proof their investment against vendor lock-in. More importantly, it opens the door to equity. Students from underfunded schools gain access not only to free content but also to high-quality assessments that measure progress fairly and transparently.
Open content can promote access, inclusion, and fairness, helping institutions close systemic gaps. However, when it comes to OER, it’s not simply permissions that count—it’s content. Research suggests that using knowledge-based OERs can help educators completely close the equity gap. The same simply can’t be said of skills-based OERs.
If you’re looking for more resources on open educational books, tools, and programs, check out these helpful articles on the TAO blog:
If you’re committed to closing the achievement gap, OER is a powerful lever—but it only works when paired with the right tools. Open resources give every student access to the same high-quality content, regardless of ZIP code or budget. TAO takes that a step further by delivering assessments built on open standards, so schools can integrate OER seamlessly into testing and instruction.
No silos, no vendor lock-in—just a flexible system that helps teachers measure learning and adapt to student needs. Schedule a demo to see how TAO helps turn OER into real equity in the classroom.