## Reflection: Developing a Conceptual Understanding Change Unknown Word Problems - Section 1: Introduction/Hook

In this lesson, I use pictures to help students understand a word problem.  In change unknown word problems, it is often difficult for students to understand the "action" in the problem and they write inaccurate number sentences or simply add the two numbers since they can't visualize the problem.  When students draw a picture they are able to  more concretely understand the problem and are more likely to write an accurate number sentence.

At the beginning of the school year, I encourage students to draw a picture for all of their problems so that they get used to concretely illustrating a problem before writing a number sentence.  By the end of the year, students who still need this tool use it, while others who have a deeper conceptual understanding simply visualize the problem in their head and don't draw pictures.

When introducing a new skill like change unknown problems, I go back to drawing pictures because it helps students to develop a conceptual understanding of what a change unknown problem is and how to write an appropriate number sentence.

Drawing pictures to explain a word problem
Developing a Conceptual Understanding: Drawing pictures to explain a word problem

# Change Unknown Word Problems

Unit 6: Three-Digit Addition and Subtraction
Lesson 11 of 13

## Big Idea: Students identify, develop, use, and share their own strategies for solving change unknown word problems.

Print Lesson
11 teachers like this lesson
Standards:
Subject(s):
Math, Differentiation, Number Sense and Operations, addition, subtraction, place value strategies
55 minutes

### Caitlin Vaughan

##### Similar Lessons

###### A Grinchy Christmas
1st Grade Math » Properties of Addition and Subtraction
Big Idea: This Grinch inspired lesson pushes 1st graders to attempt 2 part story problems. It also is a great way to introduce the topic in 2nd grade!
Favorites(9)
Resources(14)
New Orleans, LA
Environment: Urban

###### 10, 20, 100 Day 2
1st Grade Math » Complements of 10 and 20
Big Idea: Students will use dice to roll a number and then find the complement to make 10, 20 or 100.
Favorites(1)
Resources(15)
Waitsfield, VT
Environment: Suburban

###### The Recipe for a Great Word Problem
2nd Grade Math » Addition and Subtraction Basic Training
Big Idea: The big idea of this lesson is to have students write their own word problems to help them have a better understanding of mathematical operations, as they relate to real world scenarios.
Favorites(88)
Resources(14)
Pepperell, MA
Environment: Rural