The OECD E2030 conducted a series of three math workshops: the first focused on assessment and student engagement (November 29, 2021); the second on pedagogy (math workshop held on January 27, 2022); and the third on mathematics textbooks, including e-textbooks (March 23, 2022).

Mr. Ikkyu Yanagimoto, a former math teacher and the current Vice Principal of Sabae City Toba Elementary School in Fukui prefecture, as well as an Empowerment Partner of the Kyoso Sankaku Network, shared his experience at the second math workshop, specifically addressing the issue of curriculum overload in second-year junior high school math.

Mr. Yanagimoto's presentation was titled "Addressing Curriculum Overload through Big Ideas: An Example from Second-Year Junior High School Math." He explained how he tackled this issue by designing a cross-disciplinary curriculum centered around big ideas, which allowed for a reduction in instructional time for topics such as probability, functions, and statistics in math. He emphasized the importance of connecting these mathematical concepts to non-mathematical subjects. By following the textbook order, these topics would require a total of 20 lesson hours. However, with the cross-disciplinary curriculum Mr. Yanagimoto developed with his colleagues, they were able to cover these topics in just 6 hours by utilizing big ideas as a guiding principle.

The cross-disciplinary curriculum he designed combined mathematics and history. He began the class by introducing a real-life issue that is highly relevant and familiar to Japanese students: earthquakes. Building on the concept of probability learned in the previous class, he connected it to the theme of earthquakes, making it the focal point of the day's lesson.

To enhance the lesson, Mr. Yanagimoto invited an external expert, a science communicator from a science museum, to join the class remotely. The expert introduced the theme of one of the museum's exhibitions, "Predict the Unknown." In groups, students were asked to think about hazards other than earthquakes and create a hazard map, indicating how the level of social concern would change over time.

Students used their existing knowledge to come up with topical or historical topics such as Covid-19, car accidents with automated cars, and extreme fatigue or death from overwork or lack of work-life balance.

Mr. Yanagimoto highlighted that if the math topics of "probability," "functions," and "statistics" were taught solely based on the course of study and textbook exercises, in addition to incorporating cross-disciplinary topics such as time evolution/history, it would require approximately 20 hours. However, through his design of the cross-disciplinary curriculum, he was able to cover these topics in just 6 hours. The key principle he emphasized was the utilization of "big ideas" as connectors across different disciplines. In this particular class, the focus was on two big ideas: "change" and "prediction."

According to the OECD curriculum analysis report Curriculum Overload: A way forward, big ideas are fundamental concepts that appear in curricula and are crucial across multiple learning areas. They provide a clear focus for teachers when deciding what to prioritize without being overly prescriptive in terms of content. Introducing these big ideas helped students understand and apply probability, functions, and statistics by predicting the likelihood of an earthquake with its epicenter in Tokyo occurring in the future. By engaging with these topics in the context of a real and existing threat, students not only recognized the relevance of these concepts in understanding and improving society's well-being but also became motivated to learn math as they understood the purpose behind it. This example illustrates how a cross-disciplinary curriculum can alleviate curriculum overload for teachers and simultaneously enhance student motivation and engagement. It also emphasizes the significance of teacher agency, creativity, and the ability to establish connections across different disciplines when designing engaging classes.

For the complete presentation by Mr. Yanagimoto, please refer to the attached PowerPoint slide. His examples are planned to be incorporated into the upcoming OECD E2030 mathematics curriculum analysis publication.