Unit Plan 31 (Grade K Math): Add/Sub within 10—Choice of Tools

Focus: Students choose appropriate tools—counters, drawings, or equations—to solve addition/subtraction within 10 and explain their thinking.

Grade Level: K

Subject Area: Mathematics (Operations & Algebraic Thinking)

Total Unit Duration: 5 sessions (one week), 30–40 minutes per session

I. Introduction

Students explore multiple ways to solve add/subtract situations within 10 and practice matching stories to tools. They act out problems, build with counters, draw quick pictures, and write simple equations that fit their models. Emphasis is on choosing tools (MP.5) and explaining why the choice makes sense.

Essential Questions

• How do I decide whether to add or subtract in a story problem?
• Which tool (counters, drawings, equation) helps me solve and explain best?
• How do I check that my equation matches my model and my story?

II. Objectives and Standards

Learning Objectives — Students will be able to:

1. Represent and solve addition and subtraction story problems within 10 using counters, drawings, or equations.
2. Write and read simple equations with +, −, and = that match a story/model.
3. Choose tools strategically (MP.5) and justify their choice.
4. Explain and check solutions by acting out, recounting, or using the inverse story.

Standards Alignment — CCSS Kindergarten (threaded across the unit)

• K.OA.1: Represent addition and subtraction with objects, fingers, drawings, and equations within 10.
• K.OA.2: Solve addition and subtraction word problems within 10 using objects/drawings to represent the problem.
• Mathematical Practices: MP.5 (use appropriate tools strategically) emphasized; MP.1 (persevere), MP.3 (construct arguments), MP.6 (precision) threaded.

Success Criteria — Student Language

• I can choose a tool that fits the problem.
• I can make a model and write an equation that match the story.
• I can explain my strategy and check my work.