# Lesson 7

Números hasta 100,000

## Warm-up: Conteo grupal: De 1,000 en 1,000 (10 minutes)

### Narrative

The purpose of this Choral Count is for students to count on by 1,000 from multiples of one hundred and notice patterns in the count. As students count, they may notice that the digit in the hundreds place does not change after each new number is said. This is important when considering the magnitude of the number and will support reasoning in the next section as students compare and order numbers. These understandings also help students develop fluency and will be helpful later in this lesson when students read and write numbers within 1,000,000.

### Launch

• “Contemos de 1,000 en 1,000, empezando en 3,400” // “Count by 1,000, starting at 3,400.”
• Record as students count.
• Stop counting and recording at 23,400.

### Activity

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

### Activity Synthesis

• “¿Qué partes de los números se mantienen iguales mientras contamos?” // “What parts of the numbers stay the same each time we count?” (The digits in the hundreds, tens, and one place remain the same each time.)
• “¿Cuándo van a cambiar esos dígitos?” // “When will these digits change?” (The digit in the hundreds, tens, and ones place will never change because we are counting by 1,000 each time.)

## Activity 1: Contemos y escribamos números (20 minutes)

### Narrative

In this activity, students approach 10,000 by counting up in different ways. Each count ends by reaching 10,000. Students count by different amounts and describe patterns and relationships between numbers. The activity is designed to highlight familiar counting patterns as a way to support naming and writing multi-digit numbers. The final questions in the task ask students to consider the magnitude of each number in relation to 10,000.

When students count by large numbers and examine the counted numbers, they observe patterns in how the different digits in the numbers change (MP7).

Representation: Access for Perception. Provide access to a variety of tools that students may use to approach the task. These might include: a class set of base-ten blocks, colored pencils to color-code place values or highlight the digit that changes, and a visual display reminding students of sketches they can make to represent numbers with thousands and ten-thousands.
Supports accessibility for: Conceptual Processing, Visual-Spatial Processing, Attention

### Launch

• Groups of 2
• “Lean las instrucciones del problema 1 y cuéntenle a un compañero qué entienden que hay que hacer” // “Read the directions for problem 1 and share your understanding of the directions with a partner.”
• “Antes de comenzar, ¿qué preguntas tienen?” // “What questions do you have before we begin?”

### Activity

• 5 minutes: independent work time
• 10 minutes: partner work time
• As students work,
• listen for how students say the numbers and support them in using place value understanding to say the numbers correctly.
• look for use of extra digits when writing numbers (for example, students write 90,500 instead of 9,500) and support students with making the revisions by having them say the numbers.

### Student Facing

Sigue las instrucciones y escribe los números en los espacios dados. El primer número ya está escrito.

1. Cuenta de 1,000 en 1,000

5,000 , _____________, _____________, _____________, _____________, _____________

2. Cuenta de 100 en 100

9,500 , _____________, _____________, _____________, _____________, _____________

3. Cuenta de 10 en 10

9,950 , _____________, _____________, _____________, _____________, _____________

4. Cuenta de 1 en 1

9,995, _____________, _____________, _____________, _____________, _____________

1. Diez mil es 1 más que _____________.

2. Diez mil es 1,000 más que _____________.

3. Diez mil es 10 más que _____________.

4. Diez mil es 100 más que _____________.

### Student Response

If students interpret the part a of the last problem to mean “name a number that is 10,000 more than 1,” consider clarifying by asking: “¿El número 10 es 1 más que cuál número?” // “The number 10 is 1 more than what number?” and “¿El número 100 es 1 más que cuál número?” // “The number 100 is 1 more than what number?” Then, restate the sentence in part a: “¿Diez mil es 1 más que cuál número?” // “Ten-thousand is 1 more than what number?”

### Activity Synthesis

• “¿En qué se parecen contar de 100 en 100 y de 1,000 en 1,000 a contar de 1 en 1 y de 10 en 10?” // “How is counting by 100 and 1,000 like counting by 1 and 10?” (When counting by thousands, only the thousands change. This is also the case when counting by ones, tens, and hundreds.)
• Have students share their answers for the last problem.
• Consider asking: “¿Alguien puede expresar de otra forma lo que _____ compartió?” // “Who can restate what _____ shared?”
• If needed, discuss the placement of the comma in each number.

## Activity 2: Muchos miles (15 minutes)

### Narrative

In this activity, students work within 100,000 and determine how many thousands and ten-thousands are in each number. When students use strategies that are based on place value they are looking for and making use of structure (MP7).

MLR8 Discussion Supports. Students should take turns deciding the number of thousands the given number has and explaining their reasoning to their partner. Encourage students to challenge each other when they disagree. Display the following sentence frames for all to see: Observé _____, entonces yo . . .” // “I noticed _____ , so I . . .” and “Estoy en desacuerdo porque . . .” // “I disagree because . . . .”

### Launch

• Groups of 2
• “Lean en silencio las instrucciones de la primera pregunta” // “Read the directions for the first question silently.”
• Call on 2 different students to restate the directions in their own words.

### Activity

• 5 minutes: independent work time
• 5 minutes: partner work time

### Student Facing

1. Completa la tabla para mostrar cuántas unidades de mil hay en cada número. En la última fila, escribe tu propio número de cinco dígitos.

número número de unidades de mil nombre en palabras $$\phantom{\text{number of }}$$ $$\phantom{\text{ten-thousands}}$$
10,000 10 diez mil
20,000
90,000
11,000
27,000
98,000
2. Con tu compañero, nombra cada número en palabras (por ahora no llenes la última columna).

3. En la fila primera fila (en el encabezado) de la última columna, escribe “número de unidades de diez mil”. Completa la tabla para mostrar cuántas unidades de diez mil hay en cada número.

4. Estos son cuatro números:

20,500

51,300

82,050

5,970

1. ¿Cuál número tiene un 5 en la posición de las unidades de mil?
2. ¿Cuál número tiene un 5 en la posición de las unidades de diez mil?

### Student Response

If students identify 27,000 as having only 7 thousands instead of 27 thousands in the first problem, consider asking, “¿Cómo podríamos representar 27,000 usando solamente bloques de mil?” // “How would we represent 27,000 with only thousands blocks?” and “¿Esto les ayuda a pensar en el número de bloques de mil que podríamos usar para construir al 20,000?” // “Does this help you think about the number of thousand blocks we might use to build 20,000?” Students may also need to build or sketch representations to support this reasoning.

### Activity Synthesis

• Read each of the numbers in the table chorally. For additional practice saying numbers, have students read the numbers in the last problem as well.
• Discuss students’ responses to the second and fourth columns.
• “¿Cómo se relaciona el número de unidades de mil con el número de unidades de diez mil?” // “How are the number of thousands related to the number of ten-thousands?” (There are 10 groups of thousands in every ten-thousand.)
• If needed, consider referring to the 10,000 chart created in the last lesson or using base-ten blocks to clarify the relationship between the number of thousands and the number of ten-thousands in each five-digit number.

## Lesson Synthesis

### Lesson Synthesis

“Hoy trabajamos con números que tienen unidades de diez mil. Identificamos unidades de mil y de diez mil en distintos números” // “Today we worked with numbers with ten-thousands. We identified thousands and ten-thousands in numbers.”

Write 68,100 for all students to see. Recite the number chorally to practice reading numbers.

“¿Cómo podemos saber cuántas unidades de mil hay en un número?” // “How can we tell the number of thousands in a number?” (We can count by 1,000 to the number, build or draw the number using thousands, or look at the digits in the thousands place (and higher) of the number.)

“¿Cómo podemos encontrar el número de unidades de diez mil que hay en un número?” // “How do we determine the number of ten-thousands in a number?” (We can count by 10,000 to the number, sketch a diagram to represent the number, or look at the digit in the ten-thousands place (and higher).)