Lesson 2

In a previous lesson, students were introduced to number lines and represented the location of numbers with labeled tick marks and points within 20.

In the first activity, students each get a number and work together to decide how to place their numbers on a class number line, thinking about the importance of equal spacing and sequencing numbers from left to right. In the second activity, students analyze different student-created number lines and suggest revisions that should be made to make each number line a more accurate representation. Throughout the lesson, students deepen their understanding of the structure of the number line by attending to precision and thinking about the ways they can describe how to correct or improve a number line to others (MP3, MP6).

Activity 1: Class Number Line

• Hang yarn across the classroom (yarn should be hung taut to resemble a line) for students to hang their number cards on.
• Create a set of number cards from the blackline master.
• Fold the number cards so they can be hung on the line.