# Lesson 8

Comparemos pesos

## Warm-up: Observa y pregúntate: Balancín (10 minutes)

### Narrative

The purpose of this warm-up is to elicit ideas that students have about weight, which will be useful when students compare the weights of objects in a later activity. Consider reading aloud and discussing books that explore weight, such as:
• Mighty Maddie by Stuart J. Murphy
• Just A Little Bit by Ann Tompert
• The Seesaw by Judith Koppens
• Balancing Act by Ellen Stoll Walsh

### 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?

### Activity Synthesis

• “Digan algunas cosas que sean pesadas” // “What are some things that you think are heavy?”
• Share and record responses.
• “Digan algunas cosas que sean livianas” // “What are some things that you think are light?”
• Share and record responses.

## Activity 1: Comparemos los pesos de cajas y bolsas (15 minutes)

### Narrative

The purpose of this activity is for students to describe and compare the weights of objects. In the first example, students work with two identical boxes and consider the difference in weight between a box with books in it and one without.  In the second example, students discuss ways to compare the weights of objects when it’s not clear which object is heavier. Students may only describe the weight of one of the objects when comparing. (“The book is heavier.”) The teacher shares the complete comparison statement. (“The book is heavier than the pencil.”) To develop their conceptual understanding of weight as an attribute, it is important that all students are able to feel the bags in the second example in this activity. The bags can either be passed around so that each student can feel them, or multiple bags can be made.

### Required Preparation

• Prepare 2 boxes, one filled with books, labeled “1,” and one empty box, labeled “2.”
• Prepare 2 closed bags, one containing a few crayons, labeled “1,” and one filled with rocks or other heavy objects, labeled “2.”

### Launch

• Groups of 2
•  Display box 1 and box 2.
• “¿Qué observan? ¿Qué se preguntan?” // “What do you notice? What do you wonder?” (Students may notice: The empty box is light. There is a lot of stuff in the box, so that box must be heavier. Students may wonder: Is the empty box lighter than the box that is filled with books? Is the box with books heavier than the empty box?)
• 30 seconds: quiet think time
• 1 minute: partner discussion
• Share responses.
• If no student compares the weights of the boxes, ask: ¿Cuál caja creen que es más pesada? ¿Por qué piensan eso?” // “Which box do you think is heavier? Why do you think that?”
• 30 seconds: quiet think time
• 1 minute: partner discussion
• Share responses.
• “¿Cómo pueden descifrar cuál caja es más pesada?” // “How could we figure out which box is heavier?” (We could pick them up and feel which one is heavier.)
• 30 seconds: quiet think time
• 1 minute: partner discussion
• Share responses.
• Choose one student to hold each box and share with the class.
• “Usamos las palabras ‘más pesado que’ y ‘más liviano que’ cuando comparamos el peso de los objetos. Háblenle a su pareja sobre las cajas usando las palabras ‘más liviana que’” // “We use ‘heavier than’ and ‘lighter than’ when we compare the weights of objects. Tell your partner about the boxes using ‘lighter than.’”
• 30 seconds: quiet think time
• 30 seconds: partner discussion
• Monitor for students who say the complete comparison statement. If students only say “The empty box is lighter,” prompt by asking “¿Más liviana que qué?” // “Lighter than what?”
• Share responses

### Activity

• Display bags 1 and 2.
• “Aquí hay dos bolsas, pero no podemos ver qué hay adentro. ¿Cuál bolsa es más pesada?” // “Here are 2 bags, but we can’t see what is inside. Which bag is heavier?”
• 30 seconds: quiet think time
• Share responses.
• “¿Cómo podemos descifrar cuál bolsa es más pesada?” // “How could we figure out which bag is heavier?” (We could pick them up and feel which one is heavier.)
• 30 seconds: quiet think time
• 1 minute: partner discussion
• Share responses.
• Pass the bags around so that each student can hold both bags to compare the weights.

### Activity Synthesis

• “Ahora que todos sentimos las bolsas, ¿cuál bolsa es más pesada?” // “Now that we have all felt the bags, which bag is heavier?”
• Share responses.
• “Háblenle a su pareja sobre las bolsas usando las palabras ‘más liviana que’” // “Tell your partner about the bags using ‘lighter than.’”
• Share responses.
• “Podemos sostener objetos en nuestras manos para descubrir cuál objeto se siente más pesado y cuál se siente más liviano” // “We can hold objects in our hands to figure out which object feels heavier and which feels lighter.”

## Activity 2: Comparemos pesos (10 minutes)

### Narrative

The purpose of this activity is for students to practice comparing the weights of two objects by feel and using comparison language. Any classroom objects can be used for this activity such as books, writing utensils, baskets, office supplies, and art supplies. Students can be more comfortable using “heavy” and “heavier” than “light” or “lighter,” so vary questions between “¿Cuál objeto es más pesado?” // “Which object is heavier?” and “¿Cuál objeto es más liviano?” // “Which object is lighter?” In the activity synthesis, students practice using comparison language as they share one pair of objects that they compared. While not required, students can write the name of each object or record their comparison with a sentence, such as “La manzana es más pesada que el libro” // “The apple is heavier than the book”.

MLR8 Discussion Supports. Synthesis: At the appropriate time, give students 2–3 minutes to make sure that everyone in their group can explain which object is lighter and which object is heavier. Invite groups to rehearse what they will say when they share with the whole class.
Representation: Develop Language and Symbols. Synthesis: Make connections between the objects students share and the relationship it has to being lighter or heavier. Invite students to make a connection between the complete comparison statements and the objects they circled.
Supports accessibility for: Conceptual Processing

### Required Preparation

• Gather assorted classroom objects for students to compare.

### Launch

• Groups of 2–4

### Activity

• “Escojan 2 objetos con su compañero. Descifren y cuéntenle a su grupo cuál objeto es más pesado y cuál objeto es más liviano. Hagan un dibujo de cada objeto en su hoja de registro y marquen el objeto más pesado” // “Choose 2 objects with your partner. Figure out and tell your group which object is heavier and which object is lighter. Draw a picture of each object on your recording sheet and circle the object that was heavier.”
• 5 minutes: partner work time
• Monitor for students who use a complete comparison statement such as “The ball is lighter than the book.”

### Student Facing

Escoge 2 objetos.
Descifra cuál objeto es más pesado y cuál objeto es más liviano.

____________________

____________________

____________________

____________________

____________________

____________________

____________________

____________________

### Activity Synthesis

• Invite each group to share one set of objects that they compared. Invite students to chorally repeat the complete comparison statements in unison 1–2 times.

## Activity 3: Centros: Momento de escoger (15 minutes)

### Narrative

The purpose of this activity is for students to choose from activities that offer practice with number and shape concepts.

Students choose from any stage of previously introduced centers.

• Counting Collections
• Match Mine
• Shake and Spill

### Required Materials

Materials to Gather

### Required Preparation

• Gather materials from:
• Counting Collections, Stage 1
• Match Mine, Stage 1
• Shake and Spill, Stages 1-4

### Launch

• “Hoy vamos a escoger un centro 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” // “Think about what you would like to do.”
• 30 seconds: quiet think time

### Activity

• Invite students to work at the center of their choice.
• 10 minutes: center work time

### Student Facing

Escoge un centro.

Contar colecciones

Haz una como la mía

Revuelve y saca

### Activity Synthesis

• “Hemos aprendido diferentes formas de jugar ‘Revuelve y saca’. ¿Cuál forma de jugar ‘Revuelve y saca’ les gusta? ¿Por qué?” // “We have learned a few different ways to play Shake and Spill. Which way do you like to play Shake and Spill? Why?”

## Lesson Synthesis

### Lesson Synthesis

Display one chair and five pencils.

“Han dice que los lápices son mas pesados que la silla porque hay 5 lápices y solo 1 silla. ¿Qué piensan sobre esto?” // “Han says that the pencils are heavier than the chair because there are 5 pencils and only 1 chair. What do you think about?” (There are more pencils, but they are small and light. The chair is probably heavier even though there is only one chair.)

“¿Qué puede hacer Han que le ayude a descifrar si la silla es más pesada o los lápices son más pesados?” // “What can Han do to help him figure out if the chair or the pencils are heavier?” (He can hold the chair and the pencils and see which one feels heavier.)