Consider below, this teacher teaches two sections of Math 7. Yes, the teacher can check the expression for differences, but Gradebook allows you to display the section number which is often more useful.
Steps:
1. Click on Tools --> Preferences in the Menu Bar.
2. In the pop-up window, navigate to the Section tab, choose section number as the way to distinguish between sections and hit save.
The result is much easier to read and distinguish between sections.