Lesson 20

This Number Talk encourages students to think about grouping numbers. When finding the total value of a set of coins, students grouped like coins and used skip counting or counting on to find the amount of money represented. This string provides an opportunity for students to practice these strategies. These understandings help students develop fluency and will be helpful later in this lesson when students find and compare the values of coin collections.

• Display one expression.
• “Hagan una señal cuando tengan una respuesta y puedan explicar cómo la obtuvieron” // “Give me a signal when you have an answer and can explain how you got it.”
• 1 minute: quiet think time

• Record answers and strategies.
• Keep expressions and work displayed.
• Repeat with each expression.

• “¿Cómo nos puede ayudar el tercer problema a pensar en el último?” // “How could the third problem help us think about the last one?” (\(25 + 25 = 50\) and \(20 + 30 = 50\), and they both had 15, so the only difference was the 6 and 7.)

The purpose of this activity is for students to learn stage 1 of the Would You Rather? center. Students compare the value of two sets of coins. The first partner spins and identifies a number of coins. They write a question that compares the coins they spun to a collection of coins they make up. Their partner makes a choice of which collection of coins they would rather have and explains why in terms of the units. 

• Groups of 2
• Give each group a spinner and a recording sheet.
• “Vamos a conocer un centro nuevo llamado ‘¿Qué prefieres?’. Vamos a comparar el valor de colecciones de monedas. Juguemos una ronda juntos” // “We are going to learn a center called Would You Rather. We will compare the value of coin collections. Let's play a round together.”
• “Un compañero gira la ruleta para obtener un grupo de monedas. Ese compañero identifica las diferentes monedas que hay en la colección y cuenta cuántas hay de cada una. Después, escribe una pregunta para comparar la cantidad de monedas que sacó con un grupo diferente de monedas que se inventa” // “One partner spins to get a group of coins. They identify the different coins in the collection and count how many of each. Then, they write a question that compares the amount they spun to a different group of coins that they make up.”
• Demonstrate by spinning the spinner and drawing a group of coins. Provide example questions that show keeping the number of coins the same and changing the name of the coin or keeping the coins the same, but changing the number of each coin in the collection. For example:
  • “¿Prefieren tener 3 quarters o 3 pennies?” // “Would you rather have 3 quarters or 3 pennies?”
  • “¿Prefieren tener 4 nickels y 6 dimes o 4 dimes y 6 nickels?” // “Would you rather have 4 nickels and 6 dimes, or 4 dimes and 6 nickels?”
  • “¿Prefieren tener 1 quarter, 1 dime y 1 nickel o ningún quarter, 1 dime y 7 nickels?” // “Would you rather have 1 quarter, 1 dime, and 1 nickel or no quarters, 1 dime, and 7 nickels?”
• Invite the class discuss and share which group they would rather have.

• 8 minutes: partner work time

• Display the spinner and spin to get a coin set.
• “Invéntense una colección de monedas con un valor mayor usando el mismo número de monedas” // “Come up with a coin collection with a greater value using the same number of coins.”
• “Invéntense una colección de monedas con un valor menor usando el mismo número de monedas” // “Come up with a coin collection with a lesser value using the same number of coins.”
• Share responses. 

The purpose of this activity is for students to choose from activities that focus on finding the value of coin collections or working with shapes. 

Students choose from any stage of previously introduced centers.

• Would You Rather?
• Picture Books
• How are They the Same?

Gather materials from:

• Would You Rather?, Stage 1
• Picture Books, Stage 3
• How Are They the Same?, Stage 2

• “Ahora van a escoger centros de los que ya conocemos. Una de las opciones es seguir jugando ‘¿Qué prefieres?’” // “Now you will choose from centers we have already learned. One of the choices is to continue with Would You Rather.”
• 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

• 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

• “¿Qué les gustó de las actividades en las que trabajaron hoy?” // “What did you like about the activities you worked on today?”