Lesson 14

Escribamos y resolvamos ecuaciones con números desconocidos

Lesson Purpose

The purpose of this lesson is for students to relate equations to and write equations for multiplication situations and diagrams using a symbol for the unknown number.

Lesson Narrative

Students have worked with addition and subtraction equations with a symbol to represent the unknown number in grades 1 and 2. Students build on that work and the work with multiplication equations in the previous lesson as they encounter multiplication equations that have a symbol for the unknown number for the first time.

  • Representation
  • MLR8

Learning Goals

Teacher Facing

  • Relate equations to multiplication situations and diagrams using a symbol for the unknown number.
  • Write equations for multiplication situations and diagrams using a symbol for the unknown number.

Student Facing

  • Trabajemos con ecuaciones que tienen números desconocidos.

Required Materials

Materials to Copy

  • Card Sort Unknown Numbers, Spanish

Required Preparation

Activity 1:

Create a set of cards from the blackline master for each group of 2. 

CCSS Standards

Addressing

Building Towards

Lesson Timeline

Warm-up 10 min
Activity 1 15 min
Activity 2 20 min
Lesson Synthesis 10 min
Cool-down 5 min

Teacher Reflection Questions

How do tape diagrams help students make sense of equations in which the unknown number is in different positions?

Suggested Centers

  • Capture Squares (1–3), Stage 5: Multiply with 2, 5, and 10 (Addressing)
  • Five in a Row: Addition and Subtraction (1–2), Stage 8: Add within 1,000 with Composing (Supporting)

Print Formatted Materials

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Student Task Statements pdf docx
Lesson Cover Page pdf docx
Cool Down Log In
Teacher Guide Log In
Teacher Presentation Materials pdf docx
Blackline Masters zip