2.OA.C.3 - About the Math, Learning Targets, and Increasing Rigor

Full Standard

Determine whether a group of objects (up to 20) has an odd or even number of members, e.g., by pairing objects or counting them by 2s; write an equation to express an even number as a sum of two equal addends.

Measurement Topic

This standard is reported on the report card in these quarters as follows:

About the Math

Skills and concepts below are learning goals for this standard.

• Explain even and odd using strategies and representations including physical tools and drawings.
• Identify a group of objects as being even or odd.

Even and odd can be explained in a variety of ways. Students should be able to use various representations to explain if a number is even or odd. In the picture, color tiles and Cuisenaire rods are used to show which numbers are even. Students must have this experience before attempting to memorize which numbers are even or odd.

• Write an equation to show an even sum has the same addends (e.g., 5 + 5 = 10, 6 + 6 = 12).

We can write equations to prove that a number is even or odd. For example, 10 is even as it is equivalent to 5 + 5. Students should connect their equations to models before transitioning to "equations only." 

Essential vocabulary for this standard includes odd, even, equal groups, and pair. Visit the online dictionary Links to an external site. for vocabulary support.

Progression of Standard within Grade 2

This progression informs how to develop the standard within the grade level. This progression is provided by HCPSS Elementary Mathematics.

Progression of this Standard Across Grades

This progression is informed by the Achieve the Core Coherence Map Links to an external site.. Information is not the complete standard.

TASKS

These tasks can be used with small group or whole group instruction. 

• Distribute bags of 20 counters to students. Have them remove 6 counters and ask them to place them to place them make two sets. Pose the questions how many are in each set and do we have any leftover? Discuss how this makes six an even number. Have the students repeat this process for 11 counters. Discuss how this has one leftover and this makes 11 an odd number. In their journals, have students make a list of odd and even numbers up to 20. Pose the questions what do you notice and how would your doubles facts help you to determine if a number is even or odd? 
• Distribute a chart numbered 1 - 30 to each student and a bag of 30 counters. Have them color the odd numbers in one color and the even numbers with a different color. Provide manipulatives for the students to represent the number by placing the counters into two sets and identify the doubles fact for even numbers. Pose the question what patterns do you notice. Ask them to identify an odd number greater than 30 but less than 60. Have them partner up and build the number using the counters to justify their response. Continue to identify more numbers between 30 and 60 that could be even or odd and build the number. For even numbers, identify the doubles fact. Chart these numbers as a class.
• Annie said that 15 is an odd number. Is she correct? Justify your answer.
• Write 2 odd numbers between 10 and 30. How do you know they are odd? Write 2 even numbers between 20 and 40. How do you know they are even?
• Does doubling a number always lead to an even number sum? Use examples to support your answer.
• Just by looking at this array, can you tell if it’s an even or odd total? Explain your thinking.

⇿ ⇿ ⇿ ⇿ ⇿ ⇿ ⇿ ⇿ ⇿
⇿ ⇿ ⇿ ⇿ ⇿ ⇿ ⇿ ⇿ ⇿

• There are 20 pencils in the package. Jenn sharpens 3 of them. How many are unsharpened? Is this amount even or odd? How do you know?

SLIDE-BASED TASKS 

  These links are HCPSS created instructional tasks. These tasks are provided in Google slides. These tasks should be used for inspiration and resources, but instruction should start with students having the opportunity to engage with the math first (often involving physical and/or visual models) followed by discussion and explicit instruction to ensure student understanding.

Additional Tasks 

  These links provide instructional ideas connected to this standard. 

• Red and Blue Tiles (Illustrative Math)
• Buttons odd and even Links to an external site. (Illustrative Math)
• Library Task Download Library Task
  (Utah Core Academy Lesson)
• Are You Odd or Even Download Are You Odd or Even
  (Utah Core Academy Lesson)
• Fruity Numbers Download Fruity Numbers
  (Utah Core Academy Lesson)
• Odd and Even Download Odd and Even
  (Utah Core Academy Lesson)
• Two of Everything Download Two of Everything
  (Utah Core Academy Lesson)
• Back to School Night Download Back to School Night
  (Utah Core Academy Lesson)
• Bumpy or Not Bumpy, Pg. 23 Links to an external site. (Georgia Department of Education Lesson)
• Additional Ideas

Tasks From Print Resources

  These publications have been provided for each school. They are typically stored in team closets or the media center. Check with your team leader if you cannot find them. 

Print Resources

Book Thumbnail	Book Title	Grade	Pages
	Teaching Student-Centered Mathematics	K-3	292 (Bumpy or Not Bumpy, Activity 10.18)
	Hands-On Standards	1-2	84-85 (Even and Odd Number Patterns)
	Groundworks: Reasoning about Number	2	48-51 (The Third Clue) 56-62 (House Numbers)
	Math Intervention: Building Number Power	PK-2	74-78 (Even and Odd)
	Number Sense	1-2	121 (How Could it Happen?) 138-142 (What Number am I?) 143-146 (My Two Numbers)
	Math In Practice Teaching Second-Grade Math	2	Module 3

Centers

  These print resources can be used during independent or center time. These resources could also be used as lesson seeds.

• Estimate Even and Odd Download Estimate Even and Odd
  (HCPSS-adapted resources)
• Even Odd Counters Download Even Odd Counters
  (HCPSS-adapted resources)

INDEPENDENT PRACTICE/HOMEWORK/ASSESSMENT

  These resource sheets can be used for independent practice, homework, or assessment. They are intended to reinforce procedures and concepts. They should not be used as a source of direct instruction or whole-group practice.

• Even and Odd Numbers a Links to an external site.
• Even and Odd Numbers b Links to an external site.
• Explain Even or Odd: Jellybeans Links to an external site.
• Explain Even and Odd Links to an external site.
• Identify and Write Equations to Represent Even Numbers Links to an external site.
• Identify and Write Equations to Represent Even Numbers_2 Links to an external site.
• Identify and Write Equations to Represent Even Numbers_3 (performance task) Links to an external site.

Full Standard

Determine whether a group of objects (up to 20) has an odd or even number of members, e.g., by pairing objects or counting them by 2s; write an equation to express an even number as a sum of two equal addends.

Measurement Topic

The standard is reported on the report card through these measurement topics. Expand the measurement topic for a description of what students who meet expectation are able to do.

2nd Grade Students Learning 2nd Grade Standards by Measurement Topic

1st Students Learning 2nd Grade Standards by Measurement Topic

2OA3 Anecdotal Data Collection Tool Links to an external site.

Visit the SBIR (Standards Based Instruction and Reporting) page in Course Essentials for more information and clarification. 

Rubric (for thinking and reasoning evidence)

Use this rubric for observation and constructed responses (tasks that require explanation, justification, and/or representation).

Rubric for Tasks (pdf) Links to an external site.

Exemplars for this standard

Use the links below to access a task for this standard as well as student work samples that are examples of what it might look like for a student who MEETS EXPECTATIONS, is MAKING PROGRESS, and/or is MAKING LIMITED/NO PROGRESS.

Explain Even or Odd: Jellybeans

• Printable Assessment Task Links to an external site.
  • Related Instructional Task: Jellybeans Links to an external site.
• Student Exemplars Links to an external site.