In this lesson, students learn about converting numerical information into graphical representations, specifically using pie charts. The teacher discusses how to represent data, such as production percentages from different countries, and demonstrates cross multiplication to determine equivalent values in degrees. An example is provided, where 5% of a total is calculated as equivalent to 18 degrees in a circle. The lesson emphasizes the importance of being able to convert percentages into graphical forms and their applications in real-world data.