Announcing Bridges in Mathematics Third Edition!

See what’s new in the curriculum!

Four of eight units are devoted to addition and subtraction within 20. They help students gain fluency with facts to 10 and develop increasingly sophisticated strategies for solving addition and subtraction combinations to 20. During these units, students model, solve, and pose a wide variety of word problems to construct meaning for the operations of addition and subtraction, as well as an understanding of how the two are connected.

Two of the eight units focus on place value, extending the counting sequence to 120 as students learn to think of whole numbers between 10 and 100 in terms of tens and ones. Much of the work in these units engages first graders in developing, discussing, and using efficient, accurate, and generalizable methods to add within 100 and subtract multiples of 10.

The remaining two units revolve around geometry and measurement. The geometry unit challenges children to identify, describe, construct, draw, compare, compose, and sort shapes. Students also learn about fractions in the context of two-dimensional shapes. The measurement unit provides ample opportunity for students to develop an understanding of the meaning and processes of measuring time and length as they conduct duration experiments; construct, fly, and measure the flight distances of paper gliders; and investigate some of the many ways in which they have grown and changed since they were born.

## Content Outline and Samples

### Unit 1

#### Numbers All Around Us

• Counting & Data with Popsicles
• Meet the Number Rack
• Part-Part-Whole to Ten
• Adding & Subtracting to Ten with the Number Rack

### Unit 4

#### Leapfrogs on the Number Line

• Adding & Subtracting on the Life-Sized Number Line
• Jumping by Fives & Tens
• Jumping by Fives & Tens on the Open Number Line
• Measuring, Comparing & Subtracting with Penguins

### Unit 5

#### Geometry

• Introducing Two-Dimensional Shapes
• Introducing Three-Dimensional Shapes
• Putting Shapes Together & Taking Them Apart
• Sorting & Graphing Shapes

### Unit 6

#### Figure the Facts with Penguins

• Story Problems for Basic Addition & Subtraction
• Combinations & Story Problems
• Solving for the Unknown in Penguin Stories
• Measuring & Comparing Emperor & Little Blue Penguins

### Unit 8

#### Changes, Changes

• Time & Duration
• Patterns, Structure & Change
• Measurement & Data with Paper Gliders
• Measuring Our Growth

### Number Corner

• Calendar Grid
• Calendar Collector
• Days in School
• Computational Fluency
• Number Line