The purpose of this activity is for students to solve problems involving weights that are given in the same units. Students begin by generating mathematical questions about an image of two giant pumpkins. Then weights are given for each pumpkin, and students narrow down the questions that could be answered with this information. Students then solve one of the problems generated by the class. All students can solve the same problem or each group could solve a different problem. As students are generating questions that can be answered, decide which option makes the most sense for your class.

This activity uses MLR5 Co-craft Questions. Advances: Writing, Reading, Representing.

• Display student posters around the room. If students solved different problems, group them by problem solved.
• 5 minutes: Gallery Walk
• If students solved the same problem, ask:
  • “¿En qué se parecen y en qué se diferencian las formas en las que se representó este problema en los pósteres?” // “What is the same and what is different about how this problem was represented on the posters?”
• If students solve different problems, ask:
  • “¿Qué conexiones observan entre las formas en las que se representaron estos problemas?” // “What connections do you notice about how these problems are represented?”

As students analyze descriptions of situations and make connections across representations, they practice looking for and making use of structure (MP7). As they relate the numbers and relationships in situations to those in diagrams, they reason quantitatively and abstractly (MP2). 

• Display Diagram C and Situation I.
• “¿Cómo saben que este diagrama corresponde a esta situación?” // “How do you know this diagram matches this situation?” (The 7 in the diagram represents each pack of seeds weighing 7 grams. The 84 shows that all the seed packs weigh 84 grams. The dotted lines in the diagram show that we don’t know how many seed packs there are.)
• “¿Qué ecuaciones podemos escribir que correspondan a este diagrama?” // “What equations could we write to match this diagram?” ( or )
• Discuss how students know that Diagram B and Situation E match and how the situation could be represented with equations.
• Attend to the language that students use in their explanations, giving them opportunities to describe the situations and diagrams more precisely.