Lesson 5-6

LET'S BUILD Use Patterns to Develop Fluency in Subtraction

For more help with this lesson, view the Visual Learning Animation or the Another Look Video.

MATH HELP AT HOME

Sample Additional Practice Exercise 1

Use the dot tiles to complete the equations and find a pattern. Explain the pattern you see.

A dot tile with 5 dots and 2 dots. The equation 5 minus 2 = 3. A dot tile with 5 dots and 3 dots. The equation 5 minus 3 = 2. A dot tile with 5 dots and 4 dots. The equation 5 minus 4 = 1. A dot tile with 5 dots and 5 dots. The equation 5 minus 5 = 0.

There are 5 dots in one part of the third dot tile. There are 4 dots in the other part. Use those numbers to write a subtraction equation: $5 - 4 = 1$ . There are 5 dots in one part of the fourth dot tile. There are 5 dots in the other part. Use those numbers to write a subtraction equation: $5 - 5 = 0$ . One pattern is that as the subtrahend increases, the difference decreases.

HOME ACTIVITY

Subtraction Patterns

MATERIALS

Paper, Pencil

ACTIVITY

On a piece of paper, write: $3 - 3 = ?$ ; $3 - 2 = ?$ ; $3 - 1 = ?$ ; $3 - 0 = ?$ . Have your child draw pictures for each problem, complete each equation, and then explain the pattern. (0, 1, 2, 3)