# Lesson 14

Comparemos

## Warm-up: Conteo grupal: Más 10 (10 minutes)

### Narrative

The purpose of this Choral Count is to invite students to practice counting by 10 and notice patterns in the count. In this warm-up, students have an opportunity to look for and make use of structure (MP7) of whole numbers and the base-ten system because they notice that as they count, the ones place stays the same, and the tens place changes. These understandings help students develop fluency and will be helpful later in this lesson when students compare numbers by looking at the tens place.

### Launch

• “Cuenten de 10 en 10, empezando en 3” // “Count by 10, starting at 3.”
• Record as students count.
• Stop counting and recording at 93, then count back by 10.

### Activity

• “¿Qué patrones ven?” // “What patterns do you see?”
• 1–2 minutes: quiet think time
• Record responses.

### Activity Synthesis

• “¿Quién puede describir el patrón con otras palabras?” // “Who can restate the pattern in different words?”
• “¿Alguien quiere compartir otra observación para explicar por qué ocurre ese patrón aquí?” // “Does anyone want to add an observation to explain why that pattern is happening here?”

## Activity 1: ¿Cuál es más? (15 minutes)

### Narrative

The purpose of this activity is for students to determine which number is greater. Students represent their number in any way they choose. Listen for the way students use place value understanding to compare the numbers and the language they use to explain how they know one number is more than the other (MP3, MP6). In the synthesis, students are introduced to the terms greater than and less than.

Representation: Internalize Comprehension. Synthesis: Invite students to identify which details were the most important in comparing the numbers. Display the sentence frame: “La próxima vez que compare números, prestaré atención a . . .” // “The next time I compare numbers, I will pay attention to . . . .“
Supports accessibility for: Conceptual Processing, Memory

### Required Materials

Materials to Gather

### Launch

• Groups of 2
• Give each group two paper clips and access to connecting cubes in towers of 10 and singles.
• Display 35 and 52.
• “¿Cuál número es más? Usen herramientas matemáticas para mostrar cómo pensaron. Prepárense para explicarle a su pareja cómo pensaron” // “Which number is more? Show your thinking using math tools. Be ready to explain your thinking to your partner.”
• 2 minutes: independent work time
• 2 minutes: partner discussion
• “¿Cuál es más y cómo lo saben?” // “Which is more and how do you know?” (53 is more because it has more tens than 35.)

### Activity

• “En cada turno, cada compañero puede elegir si usa la ruleta A o la ruleta B” // “Each partner can choose to use Spinner A or B for each turn.”
• 10 minutes: partner work time
MLR2 Collect and Display
• Circulate, listen for, and collect the language students use to build numbers with connecting cubes, decompose numbers into tens and ones, and compare numbers. Listen for: bigger, smaller, more, fewer, greater than, less than, ___ tens, ___ ones, tens place, ones place.
• Record students’ words and phrases on a visual display and update it throughout the lesson.

### Student Facing

• Cada compañero gira una ruleta.
• Cada compañero muestra el número de la forma que quiera.
• Compara los números con tu compañero.
• ¿Cuál número es más?

Ruleta A:

Ruleta B:

### Activity Synthesis

• “¿Qué otras palabras o frases importantes deberíamos incluir en nuestra presentación?” // “Are there any other words or phrases that are important to include on our display?”
• As students share responses, update the display by adding (or replacing) language, diagrams, or annotations.
• Remind students to borrow language from the display as needed.
• Display 93 and 26.
• “¿Cuál es más? ¿Cómo lo saben?” // “Which is more? How do you know?” (93 is more because 9 tens is more than 2 tens.)
• “Podemos decir ‘93 es mayor que 26’. También podemos decir ’26 es menor que 93’” // “We can say, ‘93 is greater than 26.’ We can also say, ‘26 is less than 93.’”
• Display 62 and 64.
• “¿Cuál número es más? ¿Cómo lo saben?” // “Which number is more? How do you know?” (64 is more. They both have 6 tens but 64 has 4 ones and that is more than the 2 ones in 62.)
• “Podemos decir que 64 es mayor que 62. También podemos decir que 62 es menor que 64” // “We can say that 64 is greater than 62. We can also say 62 is less than 64.”

## Activity 2: Elena y Noah comparan números (10 minutes)

### Narrative

The purpose of this activity is for students to attend to the value of the digits when comparing two-digit numbers. Students evaluate and critique comparison statements and the thinking behind them (MP3). They attend to the way other students reason about digits and the language they use to compare, and make revisions to help make arguments more precise and clear (MP3, MP6).

MLR8 Discussion Supports. Synthesis: Some students may benefit from the opportunity to rehearse what they will say with a partner before they share with the whole class.

### Launch

• Groups of 2
• Give students access to connecting cubes in towers of 10 and singles.

### Activity

• 6 minutes: partner work time
• Monitor for students who show their thinking using:
• connecting cubes
• drawings
• words

### Student Facing

1. Elena dice que 75 es mayor que 65 porque 7 es mayor que 6.
¿Qué piensas que quiere decir Elena?
¿Cómo podría Elena ser más clara?

2. Noah dice que 39 es mayor que 41 porque tiene un 9 y 9 es el número más grande.
¿Estás de acuerdo con Noah?
¿Qué podrías decirle a Noah para ayudarle a comparar estos números?

### Student Response

If students agree with Elena, but cannot yet articulate how she could revise her thinking, consider asking:

• “¿Estás de acuerdo con Elena? ¿Por qué?” // “Do you agree with Elena? Why?”
• “¿Puedes mostrar los números con cubos encajables? Para estos dos números, ¿qué quiere decir Elena cuando dice que 7 es mayor que 6?” // “Can you show the numbers with connecting cubes? What does Elena mean when she says 7 is greater than 6 for these two numbers?”
• “¿La afirmación de Elena sería verdadera si estuviera comparando 7 y 65? ¿Por qué sí o por qué no?” // “Would Elena’s statement be true if she were comparing 7 and 65? Why or why not?”

### Activity Synthesis

• Invite previously identified students to share.
• “Cuando comparamos números, es importante prestar atención a la posición en la que está cada dígito y qué valor tiene el dígito” // “When we compare numbers, it is important to pay attention to what place each digit is in and what value the digit has.”

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

### Narrative

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

• Write Numbers
• Grab and Count
• Five in a Row

### Required Materials

Materials to Gather

### Required Preparation

• Gather materials from previous centers:
• Write Numbers, Stages 1 and 2
• Grab and count, Stage 2
• Five in a Row, Stages 1–3

### 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.

Escribe números

Agarra y cuenta

Cinco en línea

### Activity Synthesis

• “Mai está jugando ‘Agarra y cuenta’ con su pareja. Organizó sus cubos en 4 torres de 10 y 3 unidades. Su compañera organizó sus cubos en 2 torres de 10. ¿Cuántos cubos tienen si juntan los de las dos?” //  “Mai is playing Grab and Count with her partner. She organized her cubes into 4 towers of 10 and 3 ones. Her partner organized her cubes into 2 towers of 10. How many cubes do they have together?”

## Lesson Synthesis

### Lesson Synthesis

“Hoy comparamos números de dos dígitos. ¿Cuál es mayor? ¿Cómo lo saben?” // “Today we compared two-digit numbers. Which is greater? How do you know?” (64. 64 has 6 tens and 44 has only 4 tens.)

Display 59 and 54.

“¿Cuál es menor? ¿Cómo lo saben?” // “Which is less? How do you know?” (Each has 5 tens, so I have to look at the ones place. 4 ones is less than 9 ones.)