# Lesson 5

Midamos con cubos encajables

## Warm-up: Observa y pregúntate: Midamos un lápiz (10 minutes)

### Narrative

The purpose of this warm-up is for students to compare lengths of objects and notice when they are longer, shorter, or equal to each other in length. While students may notice and wonder many things about these images, comparing the length is an important discussion point.

### Launch

• Groups of 2
• Display the image.
• “¿Qué observan? ¿Qué se preguntan?” // “What do you notice? What do you wonder?”
• 1 minute: quiet think time

### Activity

• “Discutan con su pareja lo que pensaron” // “Discuss your thinking with your partner.”
• 1 minute: partner discussion
• Share and record responses.

### Student Facing

¿Qué observas?
¿Qué te preguntas?

### Activity Synthesis

• “¿Cómo podrían describir la longitud del lápiz?” // “How can you describe the length of the pencil?” (The pencil is longer than the yellow cubes. The pencil is the same length as the purple cubes.)

## Activity 1: Longitudes de bichos rastreros y extraños (15 minutes)

### Narrative

The purpose of this activity is for students to create a connecting cube tower that is the same length as a given image. In the activity synthesis, students transition from describing the length of an object by comparing it to another object ("The earthworm is the same length as a tower of 8 cubes.") to describing the length of an object as a measurement ("The earthworm is 8 cubes long.").

### Required Materials

Materials to Gather

Materials to Copy

• Lengths of Creepy, Crawly Things, Spanish

### Launch

• Groups of 2
• Give each student connecting cubes and a copy of the blackline master.

### Activity

• “Acabamos de ver una imagen que mostraba un lápiz que tenía la misma longitud que la torre morada. Usen cubos encajables para construir torres que tengan la misma longitud que cada bicho rastrero y extraño” // “We just saw a picture that showed a pencil that was the same length as the purple tower. Use connecting cubes to build a tower that is the same length as each creepy, crawly thing.”
• 10 minutes: partner work time
• Monitor for students who carefully line up the cubes with the endpoints of the images.

### Activity Synthesis

• Invite previously identified students to share.
• Display the image of the caterpillar.
• “¿Cómo midieron la oruga?” // “How did you measure the caterpillar?” (I lined the first cube up with the end of the caterpillar. Then I added cubes until I got all the way to the other end of the caterpillar.)
• “Como la torre de 4 cubos tiene la misma longitud que la oruga y cada cubo tiene la misma longitud, podemos decir que la oruga mide 4 cubos de largo” // “Since the tower of 4 cubes is the same length as the caterpillar and each cube has the same length, we can say the caterpillar is 4 cubes long.”
• For each animal, invite students to say, “El ____ mide ______ cubos de largo” // “The ______ is ___ cubes long.”

## Activity 2: Midamos más bichos rastreros y extraños (10 minutes)

### Narrative

The purpose of this activity is for students to measure the length of images using connecting cubes. Although students have compared the lengths of objects in previous activities, length is defined in this activity since it is the first time students measure and describe the length of objects as a number of same-size length units. Students determine how many connecting cube sides long each image is. They make statements such as “The grasshopper is five cubes long.” Some students may disagree on how to measure with their partner based on where they start and end the measurement, which is the focus of the activity synthesis. When students disagree with each other and explain how they decided to measure each image, they critique the reasoning of others (MP3).

MLR8 Discussion Supports. During partner work, invite students to take turns sharing their responses. Ask students to restate what they heard using precise mathematical language and their own words. Display the sentence frame: “Te escuché decir . . . ” // “I heard you say . . .” Original speakers can agree or clarify for their partner.
Engagement: Provide Access by Recruiting Interest. Synthesis: Invite students to generate a list of additional examples of objects that can be measured with connecting cubes.
Supports accessibility for: Conceptual Processing, Visual-Spatial Processing

### Required Materials

Materials to Gather

Materials to Copy

• More Creepy, Crawly Things, Spanish

### Launch

• Groups of 2
• Give each student connecting cubes and a copy of the blackline master.
• “En la actividad anterior, encontramos la longitud de varios animales usando cubos encajables. La longitud es la medida de qué tan largo es un objeto en unidades del mismo tamaño sin espacios ni superposiciones” // “In the previous activity, we found the length of animals using connecting cubes. Length is the measure of how long an object is in same-size units without gaps or overlaps.”

### Activity

• “Usen cubos encajables para encontrar la longitud de más bichos rastreros y extraños. Primero, midan individualmente. Después, comparen con su pareja cómo pensaron. Si ustedes y su pareja no están de acuerdo en la longitud, trabajen juntos para llegar a un acuerdo. Completen cada afirmación con el número que hace que sea verdadera” // “Use connecting cubes to find the length of more creepy, crawly things. First, measure on your own. Then compare your thinking with your partner. If you and your partner don’t agree on the length, work together to come to an agreement. Complete each statement with the number that makes it true.”
• 6–8 minutes: partner work time
• As students work, consider asking:
• “¿Qué tan largo es el _____? ¿Cómo lo saben?” // How long is the _____? How do you know?”

### Activity Synthesis

• “Revisen sus medidas. ¿Encontraron las mismas medidas de longitud?” // “Check your measurements with these. Did you find the same measurements of length?”
• “Si encontraron las mismas medidas, ¿qué hicieron ustedes y su pareja para asegurarse de haber encontrado la medida de longitud correcta?” // “If you found the same measurements, what did you and your partner do to make sure you found the right measurement of the length?”
• “Si encontraron una medida diferente, ¿qué creen que pasó cuando midieron?” // “If you found a different measurement, what do you think happened when you measured?”

## Activity 3: Centros: Momento de escoger (15 minutes)

### Narrative

The purpose of this activity is for students to choose from activities that offer practice adding two-digit numbers within 100. Students choose from any stage of previously introduced centers.

• How Close?
• Target Numbers
• Five in a Row

### Required Materials

Materials to Gather

### Required Preparation

• Gather materials from:
• How Close? Stages 1–3
• Target Numbers, Stages 1–3
• Five in a Row, Stages 1–6

### Launch

• Groups of 2
• “Ahora van a escoger un centro de los que ya conocemos” // “Now you are going to choose from centers we have already learned.”
• Display the center choices in the student book.
• “Piensen qué les gustaría hacer” // “Think about what you would like to do.”
• 30 seconds: quiet think time

### Activity

• Invite students to work at the center of their choice.
• 10 minutes: center work time

### Student Facing

Escoge un centro.

¿Qué tan cerca?

Números objetivo

Cinco en línea

### Activity Synthesis

• “Diego y Elena están jugando ‘Qué tan cerca’. Diego tiene una suma de 91. Elena tiene una suma de 89. ¿Quién recibe un punto por estar más cerca de 100? ¿Cómo lo saben?” // “Diego and Elena are playing How Close. Diego has a sum of 91. Elena has a sum of 89. Who gets a point for being closer to 100? How do you know?”

## Lesson Synthesis

### Lesson Synthesis

Display an item from the classroom with connecting cubes lined up from endpoint to endpoint or use the image from the warm-up.

“Hoy medimos longitudes con cubos encajables. ¿Cuál es la longitud del lápiz? ¿Cómo lo saben?” // “Today we measured length with connecting cubes. What is the length of the pencil? How do you know?” (It is 6 cubes long. I know because the cubes are lined up with the top of the pencil and go to the end of the pencil and I counted 6 cubes.)

Display the same item from the classroom, using a connecting cube tower with extra cubes on each end of the item. For example:

“¿Cuál es la longitud del rectángulo? ¿Cómo lo saben?” // “What is the length of the rectangle? How do you know?” (It is 6 cubes long. There are extra cubes before it and after it, but those aren’t counted because they are not starting or ending on the rectangle.)

As needed, “Aunque hay algunos cubos adicionales antes y después del rectángulo, podemos medir la longitud si contamos desde el cubo que empieza en donde empieza el rectángulo. Podemos dejar de contar cuando llegamos al final del rectángulo” // “Even though there are some extra cubes before and after the rectangle, we can still measure the length by counting the cube that begins where the rectangle begins. We can stop counting when we get to the end of the rectangle.”