# Lesson 11

Ecuaciones que muestran 10

## Warm-up: Observa y pregúntate: Expresiones que muestran 10 (10 minutes)

### Narrative

The purpose of this warm-up is to elicit the idea that expressions and equations can be used to represent different compositions and decompositions of 10, which will be useful when students match compositions and decompositions of 10 to equations in a later activity. While students may notice and wonder many things about these images and expressions, the fact that each image and expression represents a total of 10 is the important discussion point. Students have seen equations in previous lessons, but the synthesis is the first time that students are introduced to the term equation.

### 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 compañero lo que pensaron” // “Discuss your thinking with your partner.”
• 1 minute: partner discussion
• Share and record responses.

### Student Facing

¿Qué observas?
¿Qué te preguntas?

$$7 + 3$$

$$5 + 5$$

$$8 + 2$$

### Activity Synthesis

• “¿Qué tienen en común las expresiones?” // “What is the same about each expression?” (They are all 10.)
• Write $$10 = 7 + 3$$.
• “Hay 10 fichas: 7 fichas rojas y 7 fichas amarillas. Podemos escribir eso así: 10 es 7 más 3. Cuando escribimos $$10 = 7 + 3$$, esto se llama una ecuación” // “There are 10 counters, 7 red counters and 3 yellow counters. We can write that as 10 is 7 plus 3. When we write $$10 = 7 + 3$$, it is called an equation.”
• Repeat the steps with the next 2 images.

## Activity 1: Emparejemos ecuaciones con tableros de 10 (10 minutes)

### Narrative

The purpose of this activity is for students to match equations to compositions and decompositions of 10 on 10-frames.

MLR8 Discussion Supports. Students should take turns matching each 10-frame to the equation and explaining their reasoning to their partner. Display and read the following sentence frames: “Observé _____, entonces emparejé . . .” // “I noticed _____, so I matched . . . .” Encourage students to challenge each other when they disagree.

### Launch

• Groups of 2
• “Unan con una línea cada tablero de 10 con la ecuación que corresponde” // “Draw a line from each 10-frame to the equation it matches.”

### Activity

• 2 minutes: independent work time
• 3 minutes: partner work time

### Student Facing

$$10 = 7 + 3$$

$$10 = 8 + 2$$

$$10 = 1 + 9$$

$$10 = 4 + 6$$

$$10 = 5 + 5$$

### Advancing Student Thinking

If students match the 10-frame with 8 red counters and 2 yellow counters to an equation other than $$10 = 8 + 2$$, consider asking:

• “¿Cuáles son las 2 partes que ves en el tablero de 10?” // “What 2 parts do you see on the 10-frame?”
• “¿Cuáles son las 2 partes que ves en cada ecuación? ¿Puedes encontrar una ecuación que muestre las mismas partes que ves en el tablero de 10?” // “What 2 parts do you see in each equation? Can you find an equation that shows the same parts that you see in the 10-frame?”

### Activity Synthesis

• Invite students to share which equation they matched to the first three 10-frames.
• As students share, ask:
• “¿Cuántas fichas hay en este tablero de 10?” // “How many counters are on this 10-frame?” (10)
• “¿Cuáles son las 2 partes que ven?” // “What are the 2 parts that you see?” (5 yellow and 5 red)
• “Hay 10 fichas: 5 fichas amarillas y 5 fichas rojas. 10 es 5 más 5” // “There are 10 counters, 5 yellow counters and 5 red counters. 10 is 5 plus 5.”
• Invite students to chorally repeat these equations in unison 1–2 times.

## Activity 2: Representemos ecuaciones con dedos (10 minutes)

### Narrative

The purpose of this activity is for students to represent equations on fingers. In this activity, students become more comfortable recognizing and representing compositions and decompositions of 10 on their fingers. In future lessons, students may choose to use their fingers to help them find the number that makes 10 when added to a given number. In the activity synthesis, students consider how 2 different drawings can represent the same equation.

Representation: Develop Language and Symbols. Synthesis: Make connections between both representations visible: fingers and equations. Invite students to identify where a number in the equation is represented in the finger drawing and vice versa.
Supports accessibility for: Visual-Spatial Processing, Organization

### Required Materials

Materials to Gather

### Required Preparation

• Each student needs at least 2 different colored crayons.

### Launch

• Groups of 2
• Give each student at least 2 different colored crayons.
• “Coloreen los dedos para mostrar cada ecuación” // “Color the fingers to show each equation.”

### Activity

• 3 minutes: independent work time
• “Mientras trabajan, díganle a su compañero cuál es el total y cuáles son las 2 partes que colorearon en cada grupo de dedos” // “As you continue working, tell your partner about the total and the 2 parts you colored in each set of fingers.”
• 3 minutes: partner work time

### Student Facing

$$10 = 6 + 4$$

$$10 = 9 + 1$$

$$10 = 5 + 5$$

$$10 = 3 + 7$$

$$10 = 8 + 2$$

$$10 = 1 + 9$$

### Advancing Student Thinking

If students color all of the fingers one color to represent $$10 = 1 + 9$$, consider asking:

• “¿Cuáles son las 2 partes que ves en la ecuación?” // “What are the 2 parts that you see in the equation?”
• “¿Cómo puedes mostrar con los dedos las 2 partes diferentes de la ecuación? ¿Cuáles dedos muestran el 1 de la ecuación? ¿Cuáles dedos muestran el 9?” //  “How can you show the 2 different parts from the equation on the fingers? Which fingers show 1 from the equation? Which fingers show 9?”

### Activity Synthesis

• Write $$10 = 8 + 2$$.
• Display a set of hands with 8 fingers colored blue and 2 fingers colored red.
• Display a set of hands with 8 fingers colored red and 2 fingers colored blue.
• “¿En qué se parecen la manera en la que Elena coloreó sus manos y la manera en la que Tyler coloreó las suyas? ¿En qué son diferentes?” // “What is the same about how Elena and Tyler colored their hands? What is different about them?” (They both colored 8 and 2. Elena colored 8 blue and 2 red. Tyler colored 8 red and 2 blue.)

## Activity 3: Centros: Momento de escoger (25 minutes)

### Narrative

The purpose of this activity is for students to choose from activities that offer practice with counting, adding, composing, and decomposing numbers.

Students choose from any stage of previously introduced centers.

• Shake and Spill
• Counting Collections
• Roll and Add

### Required Materials

Materials to Gather

### Required Preparation

• Gather materials from:
• Shake and Spill, Stages 1–3
• Counting Collections, Stage 1
• Roll and Add, Stages 1 and 2

### Launch

• “Hoy vamos a escoger centros de los que ya conocemos” // “Today we are going to choose from centers we have already learned.”
• Display the center choices in the student book.
• “Piensen qué les gustaría hacer primero” // “Think about what you would like to do first.”
• 30 seconds: quiet think time

### Activity

• Invite students to work at the center of their choice.
• 10 minutes: center work time
• “Escojan qué les gustaría hacer ahora” // “Choose what you would like to do next.”
• 10 minutes: center work time

### Student Facing

Escoge un centro.

Revuelve y saca

Contar colecciones

Lanza y suma

### Activity Synthesis

• “¿Cuál centro escogieron hoy? ¿En qué mejoraron mientras trabajaban en el centro?” // “Which center did you choose today? What did you get better at while working in the center?”

## Lesson Synthesis

### Lesson Synthesis

“Hoy usamos ecuaciones para mostrar muchas maneras diferentes de formar 10” // “Today we used equations to show many different ways to make 10.”

Write $$10 = 9 + 1$$.

Display a 10-frame with 9 red counters and 1 yellow counter.

Hold up 9 fingers.