# Lesson 2

Midamos en centímetros

### Lesson Purpose

The purpose of this lesson is for students to measure in centimeters.

### Lesson Narrative

In an earlier lesson, students learned the importance of using a standard unit to ensure that they can communicate clearly about their measurements. They learned that a single base-ten block is a centimeter cube because each edge of the cube is 1 centimeter long.

The purpose of this lesson is for students to measure in centimeters and consider more efficient ways to measure. Students use tools (base-ten blocks) that have lengths of 1 centimeter and 10 centimeters to measure the length of objects. In the warm-up and Activity 1, students begin a transition from describing their measurements of length based on the number of objects they use to describing the number of standard length units (centimeters) the objects represent. In Activity 2, students choose to measure with centimeter cubes or 10-centimeter tools (base-ten block “tens”) and explain their choices (MP5).

• Action and Expression
• MLR8

Activity 2: Midamos con herramientas de 10 centímetros

### Learning Goals

Teacher Facing

• Measure length in centimeters.

### Student Facing

• Midamos en centímetros.

### Required Materials

Materials to Gather

Materials to Copy

• Reptile Length, Spanish
• Bearded Dragon

### Lesson Timeline

 Warm-up 10 min Activity 1 20 min Activity 2 15 min Lesson Synthesis 10 min Cool-down 5 min

### Teacher Reflection Questions

What evidence have students given that shows they understand that a centimeter is a length unit? What language do they use to describe how they measure a length in centimeters?

### Suggested Centers

• Target Numbers (1–5), Stage 5: Subtract Two-digit Numbers (Addressing)
• Five in a Row: Addition and Subtraction (1–2), Stage 6: Add within 100 with Composing (Supporting)