Content Area: Math

 

Index: 4.3D Grade 7 CPI 1

 

Standard: 4.3 - Patterns and Algebra

 

Strand: D - Procedures

 

Cumulative Progress Indicator: 1 - The student will use graphing techniques on a number line

·        Absolute value

·        Arithmetic operations represented by vectors (arrows) (e.g., “-3 + 6” is “left 3, right 6”)

 

Grade: 7

 

Sample Activities:

 

·        Students use number lines to demonstrate addition of integers. They point to the number representing the amount currently in the bank and then slide their finger in the appropriate direction (right for deposits and left for withdrawals) over the distance indicated by the second amount. As they slide their finger, they use arrows to track their movements over the number line, and the teacher keeps track of the operations using positive and negative integers. Through this dual representation, students begin to understand the relationship between the addition of integers and movement along the number line.

 

·        Students are given a variety of objects whose dimensions they must determine. They are given a number line marked from 5 to 27 to simulate a broken yardstick. Students work in pairs to develop a process for determining the lengths of each of the objects to the nearest unit. After they have a workable method and have written an explanation of it in their journal, the teacher replaces the tape with another which is marked from 10 to 10. The students repeat their effort. This process helps them develop an understanding of subtraction of integers and the relationship between the operation of subtraction and distance on the number line.

 

·        Addition and subtraction of signed numbers is explored using two-colored disks and a number line. Red is used to represent positive numbers and yellow is used to represent negative numbers. When given a problem such as -3 + 5 the students place 3 yellows and 5 reds on the table. They pair up as many red and yellow disks as they can and remove them from the table. In the case of the example, 3 red and yellow disks would be paired and removed, leaving 2 red disks which represents the sum, +2.