# Lesson 2

Formemos y separemos diseños con fichas geométricas

## Warm-up: Cuál es diferente: Diseños con fichas geométricas (10 minutes)

### Narrative

This warm-up prompts students to compare four designs of pattern blocks. It draws students’ attention to the total number of pattern blocks in a design and the numbers of shapes within each group in the design, which will be useful when students create and compare pattern block designs in upcoming activities. This activity gives students a reason to attend to the features of each representation and to use language precisely (MP6).

### Launch

• Groups of 2
• Display the image.
• “Escojan uno que sea diferente. Prepárense para compartir por qué es diferente” // “Pick one that doesn’t belong. Be ready to share why it doesn’t belong.”
• 1 minute: quiet think time

### Activity

• “Discutan con su pareja lo que pensaron” // “Discuss your thinking with your partner.”
• 2–3 minutes: partner discussion
• Record responses.

### Student Facing

¿Cuál es diferente?

### Activity Synthesis

• “Encontremos al menos una razón por la que cada uno es diferente” // “Let’s find at least one reason why each one doesn’t belong.”

## Activity 1: Hagamos diseños con fichas geométricas (10 minutes)

### Narrative

The purpose of this activity is for students to compose a group of 7 objects and identify the parts and total in the design. In the activity synthesis, students share their designs and discuss that while the total number of pattern blocks stays the same, the numbers of each type of pattern block changes. As students share, the teacher records an expression to represent the parts in each design.

MLR8 Discussion Supports. Invite students to begin partner interactions by repeating the question, “¿En qué se parecen y en qué son diferentes?” // “What is the same and what is different?” This gives both students an opportunity to produce language.

### Required Materials

Materials to Gather

### Launch

• Groups of 2
• Give students pattern blocks and crayons.
• “Hagan un diseño con 7 fichas geométricas. Solo usen triángulos verdes y cuadrados anaranjados. Hagan un dibujo de su diseño y escriban números para mostrar cuántos triángulos verdes y cuántos cuadrados anaranjados usaron” // “Create a design with 7 pattern blocks. Use only green triangles and orange squares. Draw a picture of your design and write numbers to show how many green triangles and how many orange squares you used.”

### Activity

• 3 minutes: independent work time
• Monitor for students who use different numbers of triangles and squares to create a design with 7 pattern blocks.
• “Compartan su diseño con su pareja. Cuéntenle cuántos triángulos verdes usaron, cuántos cuadrados anaranjados usaron y cuántas fichas geométricas usaron en total” // “Share your design with your partner. Tell them how many green triangles you used, how many orange squares you used, and how many pattern blocks you used altogether.”
• 2 minutes: partner discussion

Mi diseño

### Activity Synthesis

• Invite 2–3 students who used different numbers of squares and triangles to share their designs.
• “¿Qué partes ven en el diseño de _____?” // “What parts do you see in _____’s design?” (There is a group of 5 green triangles. There is a group of 2 orange squares.)
• As students share, record each design with an expression. For example:
• “Antes, usamos expresiones para mostrar situaciones en las que algo se agregaba o se quitaba. También podemos escribir una expresión para mostrar las partes que vemos. Este diseño tiene 7 fichas geométricas: 5 triángulos verdes y 2 cuadrados anaranjados. Esto lo puedo escribir como $$5 + 2$$” // “In the past, we used expressions to show when something was added or taken away. We can also write an expression to show the parts that we see. This design has 7 pattern blocks, 5 green triangles and 2 orange squares. I can write that as $$5 + 2$$.”
• “¿En qué se parecen los diseños? ¿En qué son diferentes?” // “What is the same about each design? What is different?” (They each have 7 pattern blocks. They each have only squares and triangles. The designs look different. They used different numbers of squares and triangles.)
• If needed, say “Cada diseño tenía 7 fichas geométricas, pero usaron números diferentes de triángulos verdes y de cuadrados anaranjados. Seguía habiendo 7 fichas geométricas” // “Each design had 7 pattern blocks, but they used different numbers of green triangles and orange squares. There were still 7 pattern blocks.”

## Activity 2: El diseño con fichas geométricas de Han (10 minutes)

### Narrative

The purpose of this activity is for students to see 8 pattern blocks broken into 2 parts in multiple ways. Students represent each pattern block design with an expression. When students write an expression to represent the pattern blocks they reason abstractly and quantitatively (MP2).

Representation: Access for Perception. Students with color blindness will benefit from verbal emphasis, gestures, or labeled displays to distinguish between the different colors of pattern blocks.
Supports accessibility for: Visual-Spatial Processing

### Required Materials

Materials to Gather

### Launch

• Groups of 2
• Give students pattern blocks.
• “Hagan otro diseño con 7 fichas geométricas, pero solo usen triángulos verdes y cuadrados anaranjados. No usen el mismo número de cuadrados anaranjados ni de triángulos verdes que usaron antes” // “Make another design with 7 pattern blocks, using only green triangles and orange squares. Use a different number of orange squares and green triangles than you did in the previous activity.”
• 2 minutes: independent work time
• “Compartan su diseño con su pareja. Cuéntenle a su pareja cuántas fichas geométricas usaron en total y cuántos triángulos verdes y cuántos cuadrados anaranjados usaron” // “Share your design with your partner. Tell your partner how many pattern blocks you used altogether, and how many green triangles and orange squares you used.”
• 2 minutes: partner discussion.
• “Han hizo estos diseños usando 8 fichas geométricas. Escriban una expresión para mostrar cuántos triángulos verdes y cuántos trapecios rojos usó en cada diseño” // “Here are some pattern block designs that Han made with 8 pattern blocks. Write an expression to show how many green triangles and red trapezoids he used in each design.”

### Activity

• 3 minutes: partner work time

### Student Facing

Han usó 8 fichas geométricas.

1.

Expresión: ___________________________

2.

Expresión: ___________________________

3.

Expresión: ___________________________

4.

Expresión: ___________________________

### Activity Synthesis

• “¿Cuáles fueron las distintas maneras de formar 8 que encontraron en los diseños?” // “What are the different ways to make 8 that you found in the designs?” (5 and 3, 4 and 4, 6 and 2)
• Display the first and third designs.
• “¿Qué tienen en común estos diseños? ¿En qué son diferentes?” // “What is the same about these designs? What is different?” (They both show 5 and 3. They both have 8 pattern blocks. One used more red trapezoids and one used more green triangles.)

## Activity 3: Centros: Momento de escoger (20 minutes)

### Narrative

The purpose of this activity is for students to choose from activities that offer practice with addition and subtraction.

Students choose from any stage of previously introduced centers.

• Check It Off
• Find the Value of Expressions
• Bingo
• Shake and Spill

### Required Materials

Materials to Gather

### Required Preparation

• Gather materials from:
• Check It Off, Stage 1
• Find the Value of Expressions, Stage 1
• Bingo, Stages 1–3
• Shake and Spill, Stages 1–3

### 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.
• 8 minutes: center work time
• “Escojan qué les gustaría hacer ahora” // “Choose what you would like to do next.”
• 8 minutes: center work time

### Student Facing

Escoge un centro.

Márcalo

Bingo

Encuentra el valor de
expresiones

Revuelve y saca

### Activity Synthesis

• Display 4 red counters and 2 yellow counters.
• “Andre estaba jugando ‘Revuelve y saca’ y así se veían sus fichas. Al mirar todas las fichas, ¿cuáles son las dos partes que ven?” // “Andre was playing Shake and Spill and this is what his counters looked like. What are the two parts that you see in the counters?” (4 and 2)
• “Si Andre revuelve y saca 6 fichas otra vez, ¿de qué otra forma se podrían ver sus fichas?” // “If Andre shakes and spills 6 counters again, what is a different way that his counters could look?” (3 red and 3 yellow, 5 red and 1 yellow)

## Lesson Synthesis

### Lesson Synthesis

Display this pattern block design from Activity 2:

“¿Cuántas fichas geométricas hay en este diseño?” // “How many pattern blocks are in this design?” (8)

“¿Qué partes ven en este diseño?” // “What parts do you see in this design?” (6 green triangles, 2 red trapezoids)

“Una manera en la que podemos separar 8 es 6 y 2. 8 es $$6 + 2$$” // “One way that we can break apart 8 is 6 and 2. 8 is $$6 + 2$$.”

“¿Qué podemos cambiar del diseño para mostrar una manera diferente de separar el 8?” // “What can we change about the design to show a different way to break apart 8?” (Sample response: You could take away one red trapezoid and add one green triangle. Then it would show 7 and 1.)

Invite students to share and demonstrate student suggestions.