Lesson 4
One More and One Less (optional)
Lesson Purpose
Lesson Narrative
In a previous lesson, students used their knowledge of the count sequence to solve story problems involving adding and subtracting one. In this lesson, students apply this understanding to determining one more and one less than a given group of objects or numbers without a context. Students practice counting out a given number of objects. When determining one more or one less, students may recount their collection from 1 or may use their knowledge of the count sequence to know what 1 more or 1 less is. This lesson is optional because the standards do not require students to compare groups of objects or written numbers beyond 10.
If students need additional support with the concepts in this lesson, refer back to Unit 2, Section D in the curriculum materials.
 Action and Expression
 MLR8
Learning Goals
Teacher Facing
 Count out a group of up to 20 objects.
 Use knowledge of the count sequence to add and subtract one and determine one more and one less.
Student Facing
 Let’s find 1 more or 1 less.
Required Materials
Materials to Gather
 Colored pencils, crayons, or markers
 Connecting cubes
 Materials from a previous activity
 Materials from previous centers
 Twocolor counters
Materials to Copy
 Number Mat 120
 One More, One Less Mat
Required Preparation
Activity 1:
 Each group of 2 needs 1 connecting cube and at least 20 twocolor counters.
Activity 2:
 Each group of 2 needs the number mat, twocolor counters, and the connecting cube from the previous activity.
 Each group 2 also needs crayons and a copy of the 1 more, 1 less mat.
Activity 3:
 Gather materials from:
 Less, Same, More
 Math Fingers
 Tower Build
 Math Stories
 Which One
Lesson Timeline
Warmup  10 min 
Activity 1  15 min 
Activity 2  15 min 
Activity 3  15 min 
Lesson Synthesis  10 min 
Cooldown  0 min 
Teacher Reflection Questions
Print Formatted Materials
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