Lesson plan

10. Solve addition and subtraction problems involving mass (A)

teaches Common Core State Standards CCSS.Math.Content.3.MD.A.2 http://corestandards.org/Math/Content/3/MD/A/2
teaches Common Core State Standards CCSS.Math.Practice.MP1 http://corestandards.org/Math/Practice/MP1
teaches Common Core State Standards CCSS.Math.Practice.MP4 http://corestandards.org/Math/Practice/MP4
teaches Common Core State Standards CCSS.Math.Practice.MP5 http://corestandards.org/Math/Practice/MP5
Quick assign

You have saved this lesson plan!

Here's where you can access your saved items.

Content placeholder

or to view additional materials

You'll gain access to interventions, extensions, task implementation guides, and more for this lesson plan.

Lesson objective: Solve problems using the number line to show addition and subtraction strategies.

This lesson provides an opportunity for students to apply their knowledge and understanding of addition and subtraction to a real-life situation. Students are asked to show on the number line a correct strategy for solving the problem.

Key Concept students will use: 

  • representations and drawings to solve one-step situational problems involving addition and subtraction of mass.

Skills students will use:

  • place value understanding to add and subtract using a variety of strategies (Grade 3, Unit 3)
  • a number line to solve many types of addition and subtraction problems (Grade 2, Unit 2)
  • representations of a three-digit number as hundreds, tens, and ones, from left to right. (Grade 2, Unit 6)

Students engage in Mathematical Practice 1 (make sense of problems and persevere in solving them) as they use the number line to understand the problem and the meaning of the question. Students engage in Mathematical Practice 4 (model with mathematics) as they write number equations to describe how they used the number line.

Key vocabulary: 

  • grams
  • kitchen gram scale
  • number line
  • pan balance

Special materials needed:

  • kitchen gram scale
  • number line for demonstration (0 to 2,000)
  • pan balance scale and gram weights