Lesson 13

The purpose of an Estimation Exploration is to practice the skill of estimating a reasonable answer based on experience and known information. 

• Groups of 2
• Display the image.
• “¿Qué estimación sería muy alta?, ¿muy baja?, ¿razonable?” // “What is an estimate that’s too high? Too low? About right?”
• 1 minute: quiet think time

• “Discutan con su compañero lo que pensaron” // “Discuss your thinking with your partner.”
• 1 minute: partner discussion
• Record responses.

• “¿Cómo usaron la imagen, o lo que saben sobre el melón cantalupo u otros melones, como ayuda para hacer su estimación?” // “How did you use the image or what you know about cantaloupe or other melons to help you make estimates?”
• Consider asking:
  • “¿Alguien hizo una estimación menor que 100 kilogramos? ¿Alguien hizo una estimación mayor que 500 kilogramos?” // “Is anyone’s estimate less than 100 kilograms? Is anyone’s estimate greater than 500 kilograms?”
  • “Teniendo en cuenta esta discusión, ¿alguien quiere ajustar su estimación? // “Based on this discussion, does anyone want to revise their estimate?”
• Consider revealing that the actual weight of the giant cantaloupe is 344 kilograms.

This activity uses MLR4 Information Gap.

The Info Gap structure requires students to make sense of problems by determining what information is necessary, and then to ask for information they need to solve it. This may take several rounds of discussion if their first requests do not yield the information they need (MP1). It also allows them to refine the language they use and ask increasingly more precise questions until they get the information they need (MP6). This Info Gap activity provides students an opportunity to solve multiplication and division problems involving weight.

Here is an image of the cards for reference:

• Create a set of cards from the blackline master for each group of 2. 
• Keep set 1 separate from set 2.

• Groups of 2

• Display the task statement, which shows a diagram of the info gap structure.
• 1–2 minutes: quiet think time
• Read the steps of the routine aloud.
• “Voy a darles una tarjeta de problema o una tarjeta de datos. Lean su tarjeta en silencio. No se la lean ni se la muestren a su compañero” // “I will give you either a problem card or a data card. Silently read your card. Do not read or show your card to your partner.”
• Distribute cards.
• 1–2 minutes: quiet think time
• Remind students that after the person with the problem card asks for a piece of information the person with the data card should respond with “¿Por qué necesitas saber ______?” // “Why do you need to know _____ [that piece of information]?”

• 3–5 minutes: partner work time
• After students solve the first problem, distribute the next set of cards. Students switch roles and repeat the process with Problem Card 2 and Data Card 2.

• “¿Qué partes del problema les ayudaron a darle sentido a la situación?” // “What parts of the problem helped you make sense of the situation?”
• “¿Qué cantidades fueron importantes?” // “Which quantities were important?”
• “¿Alguien resolvió el problema de una manera diferente a como lo hizo su compañero?” // “Did anyone solve the problem in a different way than their partner?”

This activity uses MLR4 Information Gap.

In this activity, students solve addition and subtraction problems involving weight. Here is an image of the cards for reference:

• Create a set of cards from the blackline master for each group of 2. 
• Keep set 1 separate from set 2.

• Groups of 2

• “Usemos la misma rutina ‘Falta de información’ para resolver problemas nuevos sobre otra competencia de pesos” // “Let’s use the same information gap routine to solve new problems about another weigh-off.”
• “Voy a darles una tarjeta de problema o una tarjeta de datos. Lean su tarjeta en silencio. No se la lean ni se la muestren a su compañero” // “I will give you either a problem card or a data card. Silently read your card. Do not read or show your card to your partner.”
• Distribute cards.
• 1–2 minutes: quiet think time
• Remind students that after the person with the problem card asks for a piece of information the person with the data card should respond with “¿Por qué necesitas saber ______?” // “Why do you need to know _____ [that piece of information]?”

• 3–5 minutes: partner work time
• After students solve the first problem, distribute the next set of cards. Students switch roles and repeat the process with Problem Card 2 and Data Card 2.

• “¿Qué tipos de preguntas fue más útil haber hecho?” // “What kinds of questions were the most useful to ask?”
• “¿Hubo alguna pregunta que no supieran cómo responder?” // “Were there any questions you weren't sure how to answer?”
• “¿Cómo representaron su razonamiento después de darse cuenta de que necesitaban sumar (o restar)?” // “How did you represent your reasoning once you realized you needed to add (or subtract)?”