#### 2nd to 3rd Edition: Changes

##### Changes to the Curriculum Components

Investigations 3 has eight units per grade. Each grade level consists of approximately 140 sessions. The Differentiation and Intervention Guide (2011), and Investigations and the Common Core Standards (2012), have been integrated into the curriculum units, eliminating these 2nd edition components. Support around the Standards for Mathematical Practice, differentiation for the range of learners, and assessment have been added or expanded. A new set of online tools includes e-texts, planning tools, digital presentations, games, and provides access for families. The Student Math Handbook is now a digital-only resource called Math Words and Ideas.

Investigations 3 at Grade 3 consists of 144 Sessions across 8 units.

• Unit 1: Understanding Equal Groups (23 Sessions)
• Unit 2: Graphs and Line Plots (15 Sessions)
• Unit 3: Travel Stories and Collections (25 Sessions)
• Unit 4: Perimeter, Area, and Polygons (17 Sessions)
• Unit 5: Cube Patterns, Arrays, and Multiples of 10 (17 Sessions)
• Unit 6: Fair Shares and Fractions on Number Lines (13 Sessions)
• Unit 7: How Many Miles? (18 Sessions)
• Unit 8: Larger Numbers and Multi-Step Problems (16 Sessions)

##### Changes to the Content

Investigations 3 is based in large part on the 2nd edition of Investigations in Number, Data, and Space (2008). Content from Investigations and the Common Core Standards (2012) and the Differentiation and Intervention Guide (2011) has been integrated and, in many cases, expanded upon. Other material has been deleted, moved, or merged to create a focused, coherent, and rigorous K-5 mathematics curriculum, fully aligned to the content and practice standards of the Common Core State Standards (CCSS).

The following is not meant to be a comprehensive description of the Grade 2 curriculum, but rather a brief summary of the major changes.

##### Changes at the Unit Level

• The work on multiplication and division has expanded from one to three units. These units now include:
• More explicit connections between area and multiplication.
• Emphasis on using the distributive property to solve multiplication problems.
• Multiplying by multiples of 10.
• Multiplying and dividing within 100 with fluency.
• More emphasis on solving multi-step problems.
• The Modeling with Data unit includes work on using and interpreting pictographs.
• The three 2nd edition units focused on addition and subtraction have been consolidated into two.
• The 2-D Geometry unit no longer includes activities that use the LogoPaths software.
• The Fractions unit now includes the number line as a model for representing and comparing fractions. The unit no longer includes work on fractions of a group or the investigation on decimals.
• Work from the Patterns, Functions and Change unit (Cube Train Patterns and Marbles of Rhomaar) has been revised and integrated into the Multiplication and Division units. There is a greater emphasis in this work on the relationship between multiplication and division and solving multi-step problems.
• The 2nd edition unit focused on 3-D Geometry is no longer a part of the Grade 3 sequence.

Changes to the Ten-Minute Math Activities

• A new Ten-Minute Math activity, Closest Estimate, focuses on estimating answers to addition, subtraction, multiplication and division problems.
• The Practicing Place Value activity now includes writing numbers in expanded form and rounding numbers.
• The Quick Images activity includes a new variation, Seeing Numbers, which focuses on students writing multiplication equations that model the structure of dot arrangements.
• More or Less? is no longer a Ten-Minute Math activity.
• The Classroom Routines, Class Collection and What’s the Temperature? are no longer a part of the Grade 3 sequence.