## Lesson: Keeping Track of and Displaying Data

Introducing the Concept

Last year, students represented and compared data using tally marks. Begin with this concept to reinforce the idea that each tally mark stands for one piece of data that is collected. The connection between tally marks and summarizing data can then be shown visually.

**Materials:** chalkboard

**Preparation:** none

**Prerequisite Skills and Concepts:** Students should have basic counting skills and be able to skip-count by fives. Students should be able to make tally marks and interpret data.

Write the months of the year in large letters on the chalkboard.

Make a copy of the tally chart on a sheet of paper. You may use it later to demonstrate how to create a bar graph or line plot from existing data.