Lesson 4

The purpose of this How Many Do You See is for students to use the structure of base-ten blocks to determine the value of images (MP7). Students may name the quantity of the blocks they see by the unit each block represents (3 hundreds, 2 tens, and 4 ones), use an addition expression to name the value of each group of blocks (\(300 + 20 + 4\)), or name the number that represents the value of the blocks (324).

• Groups of 2
• “¿Cuántos ven? ¿Cómo lo saben?, ¿qué ven?” // “How many do you see? How do you see them?”
• Flash the image.
• 30 seconds: quiet think time

• Display the image.
• “Discutan con su compañero lo que pensaron” // “Discuss your thinking with your partner.”
• 1 minute: partner discussion
• Record responses as an expression using hundreds, tens, and ones.
• Repeat for each image.

• “¿Qué observaron sobre el orden de los bloques y el valor que los bloques representan?” // “What did you notice about the order of the blocks and the value the blocks represent?” (Even though the blocks were in different orders, the first two images had the same value. The order of the blocks doesn’t change the value of the blocks.)
• “Hoy vamos a leer y escribir números de tres dígitos. Presten atención a cómo el orden, o la posición, de cada dígito muestra el valor” // “Today we are going to be reading and writing three-digit numbers. Pay attention to how the order, or place, of each digit shows the value.”

The purpose of this activity is for students to use their understanding of place value to determine the number described in a riddle. Students then write the number of hundreds, tens, and ones, and represent the value as a three-digit number.

• Groups of 2
• Give students access to base-ten blocks.
• “Tengo 4 centenas, 3 unidades y 2 decenas” // “I have 4 hundreds, 3 ones, and 2 tens.”
• “¿Cuál de estos muestra el valor total escrito como un número de tres dígitos? Expliquen cómo lo saben” // “Which of these shows the total value written as a three-digit number? Explain how you know.”
• Display 432, 234, 423.
• 30 seconds: quiet think time
• 1 minute: partner discussion
• Share responses.

• “Van a resolver acertijos numéricos usando bloques en base diez” // “You are going to solve number riddles using base-ten blocks.”
• As needed, demonstrate the task with a student.
• “Por turnos, lean las pistas mientras su compañero usa bloques para formar el número” // “Take turns reading the clues, while your partner uses blocks to make the number.”
• “Asegúrense de que están de acuerdo antes de agregar cada número a la tabla” // “Make sure you agree before adding each number to the table.”
• 10 minutes: partner work time
• If students finish early, ask them to write their own riddles and trade them with other groups to solve.
• Monitor for students who recognize they need a zero when writing the three-digit number in places where there were no tens or no ones.

• Invite previously selected students to share what they noticed when writing 509 and 180.
• As needed, write 81, 801, and 810 and ask, “¿En qué se diferencian 81, 801 y 810?” // “What is the difference between 81, 801, and 810?”

The purpose of this activity is for students to find the numbers that make equations true using what they know about the meaning of the digits in three-digit numbers. In each equation, the value of the digits are presented out of place value order. Throughout the activity, encourage students to explain how they know they have made true equations using precise language about the meaning of each digit in a 3-digit number (MP3, MP6).

• Groups of 2
• Give students access to base-ten blocks.

• “En cada caso, encuentren el número que hace que la ecuación sea verdadera” // “Find the number that makes each equation true.”
• 6 minutes: partner work time
• Monitor for students who agree with Elena because:
  • 37 would mean 3 tens and 7 ones
  • if there are 3 hundreds, you need 3 digits

• Share and record responses for each equation.
• Consider asking:
  • “¿Cómo saben que su ecuación es verdadera?” // “How do you know your equation is true?”
  • “¿En qué se parecen ambos lados de la ecuación? ¿En qué son diferentes?” // “How is each side of the equation the same? How is it different?”
• Invite previously identified students to share whether they agree with Clare or Elena and why.