Problem Structures: ComparingUnit of Study: Addition and Subtractions Concepts within 10Global Concept Guide: 3 of 5

Content Development Students will work through the three day GCG on the problem

structure comparing.

Content Development “Comparison situations differ from taking from and taking

apart situations in that they involve only two discrete quantities that are not parts of a whole or related in that way..” GO Math Chapter 2 TE, pg. 73A

The terms “more” , “less” and “fewer” when used to compare can create confusion. Students generally can identify who has more, but do not recognize how many more. Students need experience with both terms.

Take the opportunity to expose students to addition sentences with missing addends as related to the problems.

6-4= 4+ =6

Day 1 Day 1 focuses on having students use snap cubes to build

number trains and compare quantities.

It is necessary for students to physically place number trains side by side and count the difference.

The Voyages lesson Compare makes a natural connection between number trains and number lines.

Day 2 After working with manipulatives on day 1, students will work

with picture representations of the problem on the second day.

Allow students to continue the use of manipulatives to model if needed, but encourage them to draw quick models (i.e. circles, tallies, etc.) to assist.

It is essential for students to see that the numerical answer can be the same for a problem whether being asked how many more or how many less, but the answer represents a different part of the problem.

Snap Cubes

Quick Picture

Day 3 Probe students and facilitate the discussion that the models

created with manipulatives are directly related to the bar model. Number lines and snap cubes can help clarify this.

Differentiate the problems given to students based on needs. For example, #4 on page 75 might be more appropriate for a below level student, where as #5 could challenge your on level and above level students.

Great discussion starter:

How does the snap cube

model compare to the

bar model?

Enrich/Reteach/Intervention

Enrich Create compare story problems Create index cards for matching scenarios with equations and

representations (including missing addends) Reteach

Grab and Go Center Big Idea 1: Activities 16/17 Intervention/Small Group

GO Math Grade 1 Chapter 2 TE - Rti Tier 2 Activities pages 69B and 73B GO Math Grade 1Rti Strategic Intervention Guide – Skill 12