In this lesson, students learned about line graphs, which are used to show how things change over time. A line graph connects data points with straight lines to display trends such as temperature over days, plant growth over months, or marks in different exams. It has two axes: the X-axis shows time, and the Y-axis shows values. Important features include a clear title, labeled axes, a proper scale, and marked data points joined by lines. Line graphs are useful for comparing data changes and understanding patterns over time.