Unit Plan 35 (Grade K Math): Measure & Compare Review

Focus: Revisit describing and comparing length and weight; make and justify claims using direct comparisons, aligned endpoints, and balance scales.

Grade Level: K

Subject Area: Mathematics (Measurement & Data)

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

I. Introduction

Students strengthen their understanding of measurable attributes by describing objects’ length and weight, then directly comparing pairs. They align endpoints to decide longer/shorter (or taller) and use balance scales or careful hand-weighing to decide heavier/lighter. Emphasis is on evidence and clear language.

Essential Questions

• What does it mean to compare two objects by the same attribute?
• How do aligned endpoints or a balance scale help us decide longer/shorter or heavier/lighter?
• How do we justify our comparison so others can see our evidence?

II. Objectives and Standards

Learning Objectives — Students will be able to:

1. Name and describe measurable attributes of objects (e.g., length, weight).
2. Use direct comparison for length (align endpoints) and weight (pan balance or careful hand compare).
3. State and record comparison statements (e.g., “The pencil is longer than the crayon”).
4. Provide evidence for comparisons using aligned endpoints, balance readings, or consistent informal units.

Standards Alignment — CCSS Kindergarten (threaded across the unit)

• K.MD.1: Describe measurable attributes of objects, such as length or weight.
• K.MD.2: Directly compare two objects with a measurable attribute in common; describe which has more/less of the attribute.
• Mathematical Practices: MP.6 (precision) and MP.5 (use tools) emphasized; MP.3 (explain/justify) threaded.

Success Criteria — Student Language

• I can tell the attribute I am comparing and use words like longer/shorter, heavier/lighter.
• I can show evidence (aligned endpoints or a balance scale) for my comparison.
• I can explain my thinking so a partner agrees my claim is true.