# 1.OA.D.7

Understand the meaning of the equal sign, and determine if equations involving addition and subtraction are true or false. For example, which of the following equations are true and which are false? 6 = 6, 7 = 8 – 1, 5 + 2 = 2 + 5, 4 + 1 = 5 + 2.
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## Summary:

The equal sign indicates more than just an answer to a math operations problem. The equal sign represents equality in equations. Clarification about the equal sign’s true meaning and use will prevent confusion when students work through equations with unknown quantities. Students should be introduced to the terminology of the equal sign by interchanging the word “equals” with the phrase “is the same as”. For example, 6+2=8 would be read, “six plus two is the same as eight”. This will help students to recognize the concept that the quantity 6+2 has the same value as the number 8. In addition, students students need to understand that the value for the entire expression on one side of the equal sign must be the same as the value for the entire expression on the other side of the equal sign. For example, in the equation 6 + 2 = 5 + ?, the missing number would be 3 because 6 + 2 = 8, so 5 + ? must also equal 8. Further understanding can be developed using equations that relate two sums on each side. For example, 2 + 6 = 3 + 5, which is a true equation.

## Understanding the Standard:

• Students need early exposure to the phrasing “the same as” when they are dealing with number problems that contain the equals sign.
• The use of models, drawings and manipulatives is especially useful in helping students to visually see that the quantity on the left side of the equal sign is the same as the quantity on the right side. False equations should be presented to students to identify, as well. For example, 6 + 0 = 6 +1.
• The concept of a balance or a see-saw is a visual tool that assists students in understanding that the amounts on either side must be the same.

## Questions to Focus Instruction:

• Can students model number sentences and show that quantities on both sides of an equal sign must be the same?
• Can students recognize when two sides of an equation (or two quantities) are not equal?
• Can students articulate with words and/or diagrams why two sides of an equation are not equal?

## Skills

Prior to: Students have mastered the knowledge that any quantity can be expressed in a variety of manners. For instance, 8 cars is the same amount as 8 kittens. The value of 8 is the same regardless of the objects that are being counted. Students have had practice in solving simple addition and subtraction problems where the equal sign is a part of the problem.

At Grade Level: Students will solve equations and explain that both sides of the equal sign have identical values, and if they do not then the equation is false.

Moving Beyond: Students will continue to solve more complex number sentences that will later involve multiplication and division.