Many math educators may not immediately see a connection between their subject and the history of eugenics, but this connection is both real and important. Eugenics did not just rely on ideology, it relied on numbers. It used charts, graphs, averages, and statistics to make biased judgments look objective. Statistical tools that are still taught in classrooms today were once used to argue that some people were more valuable than others. Eugenicists used data to rank, exclude, and justify harmful practices, often with the persuasive authority of science and math on their side. Understanding how that happened, and how to prevent it from happening again, is partially the responsible math education.
This is not just about the past. In the early 20th century, people like Francis Galton and Karl Pearson developed statistical ideas like correlation and regression to support their belief that intelligence, health, and behavior were inherited.21 These tools became central to both statistics and eugenics. As the article in Nautilus explains, the very structure of modern statistics was shaped by these efforts to define and measure human value.22 In the hands of eugenicists, statistics became a powerful way to make racism, ableism, and classism look like neutral science.23
That is why this work matters. Students are often taught to see math as objective or neutral, but the history of eugenics shows that math can be used to support harmful ideas when questions are not asked. If students do not learn to think critically about data, who collects it, why it is collected, and how it is used, they may unknowingly take part in systems that repeat these same harms or become victims of it.
This does not mean throwing out statistics. It means teaching it better. It means teaching students to ask questions, look closely at assumptions, and consider the ethical choices behind how numbers are used. This is not only anti-eugenic instruction, but also good math instruction. Students learn more deeply when they understand how math connects to real life. They also learn better when they are invited to critique, reflect, and think ethically. Angela Saini reminds us that eugenic ideas did not disappear after World War II, they often just changed form.24 This includes the continued use of standardized tests, tracking systems, and performance data that may still reflect biased assumptions.
The lessons in this unit are developed with those concerns in mind. They align with best practices in math instruction, including collaborative learning, critical thinking, and real-world application. But they also ask students to think about fairness and justice, not just accuracy. They invite students to ask questions about how data has been used in the past, and how they can use math in more thoughtful and inclusive ways.
Each of the four lessons focuses on a different area of middle school math and ties it to larger ethical questions. Lesson 1 introduces students to the concept of eugenics in accessible language and encourages them to reflect on fairness in schools. Lesson 2 integrates ratio reasoning with discussions of how percentages can be manipulated. Lesson 3 teaches students about surveys and samples, and how bias can affect the results. Lesson 4 focuses on graphs and data displays, helping students spot misleading visuals and build better ones. Together, the lessons help show students that math is not just about getting the right answer, it is about asking the right questions.
These practices echo what Peter Liljedahl describes as a 'thinking classroom,' where students develop their own strategies, critique reasoning, and build mathematical understanding through collaboration and inquiry.25 They also reflect Ruha Benjamin’s call for educators and scientists alike to recognize how structures of power and inequality are embedded in the tools we use unless we consciously disrupt them.26
Lesson 1
Learning Objectives:
Define eugenics in age-appropriate terms. Summarize how eugenics was used to sort and judge people. Identify at least one-way eugenics ideas have influenced education systems (e.g., standardized testing, segregation, tracking). Work collaboratively to analyze and respond to real-world examples of bias in education. Reflect on how fairness and inclusion matter in school and society.
Vocabulary:
Eugenics: A set of ideas in the past that claimed some people were “better” than others based on things like race, disability, or where they came from.
Bias: An unfair preference or prejudice.
Segregation: Separating people, often by race or ability.
Standardized Test: A test given the same way to many people, sometimes used to compare or rank students.
Materials:
Chart paper or whiteboard
Printed group scenario cards (included below)
Sticky notes or markers
Access to projector or board for definitions
Student handouts with reflection prompts
Lesson Procedure
Warm Up: (5–10 min): Quick write: Fair or Unfair?
Ask students to respond in writing to this question: “Imagine your teacher decides who is the smartest in the class based only on who runs the fastest. Is that fair?” Facilitate a brief discussion. Introduce the idea that people have often been judged unfairly in ways that had nothing to do with their true abilities.
Mini-Lesson (10–15 min): What Is Eugenics?
- What it was: Eugenics was a movement, popular a century ago, that claimed society could “improve” the human population by controlling who had children.
- How it worked: Proponents misused ideas from genetics and statistics to label people as “fit” or “unfit.” They encouraged those deemed “fit” to reproduce and tried to stop others from having children.
- Who it harmed: These ideas were deeply racist, classist and ableist. They led to policies like segregation, immigration bans and forced sterilizations of tens of thousands of people in the United States and elsewhere, and they provided a pseudoscientific rationale for Nazi racial laws.
- Why it matters now: Eugenics has been thoroughly discredited as bad science and unethical practice, but its assumptions still surface in some discussions about genetics and intelligence. Understanding this history helps teachers highlight how statistical tools and scientific language can be misused and ensures these harmful ideas aren’t unintentionally repeated
Group Activity (20–25 min): “Fair or Unfair?” Scenarios
Break students into 4–5 small groups. Each group receives a scenario card. Discuss if it is fair or unfair and how it could be improved.
Class Share-Out (5–10 min):
Each group shares their scenario and ideas. Teacher facilitates connections to the legacy of eugenics and the importance of fairness.
Individual Reflection (5–10 min): “How Can I Help?”
Prompt: “What is one way you can help your school be a fairer and more welcoming place for everyone?”
Students write on a sticky note and place it on the classroom “Equity Wall.”
Group Scenario Cards
A school uses only one test score to decide who gets into the advanced science program. Students who speak English as a second language score lower—not because they aren’t smart, but because the test is hard to read.
A teacher assumes that students with disabilities can’t do higher-level math, so they are not offered the chance to try.
A student from a poor neighborhood is told they are “not college material” because of their background.
A class ranks students by how well they sit still and take notes. Students with ADHD are always ranked the lowest.
In the 1920s, some scientists said people from certain countries were not smart. They helped make laws to keep them out of schools or jobs.
Individual Reflection
Prompt: What is one way you can help your school be an equitable and welcoming place for everyone?
Students write on a sticky note and place it on the classroom 'Equity Wall.'
Exit Ticket
Write one sentence answering: Why is it important to learn about unfair ideas like eugenics in history class?
Homework / Extension Activities
- Interview a family member about a time when someone was treated unfairly and how they responded.
- Research: What does your school use to decide who gets into honors or AP classes?
Teacher Notes
- Be especially sensitive when discussing race, disability, and family background. Avoid placing blame; focus on systems and ideas rather than individuals. Reinforce messages of dignity, inclusion, and student voice.
Assessment
- Participation in group activity and share-out
- Completion and thoughtfulness of reflection and exit ticket
All Printable Unit Lessons Plans
- https://drive.google.com/file/d/1WMduYxU0nsjpJdlYnXo2MACArS9JgCxh/view?usp=sharing
