Students compare numbers in this unit. At the end of this lesson, students are going to:
- Draw two quantities using base-ten blocks.
- Use the terms "greater than" and "less than" to compare two quantities.

- How does effective communication benefit from mathematics? 
- How do patterns and relationships connect in math? 
- How can identifying regularity or repetition help with problem-solving efficiency? 
- How do we represent, compare, quantify, and model numbers using mathematics? 
- What does it mean to analyze or estimate a numerical quantity? 
- What qualifies a tool or strategy as suitable for a particular task? 
- When is it appropriate to compute instead of estimate?

- Equal To: A number/quantity is the same as another. 
- Greater Than: A number/quantity is larger than another. 
- Less Than: A number/quantity is smaller than another.

- whiteboards
- markers
- erasers
- Ordering and Comparing Numbers Worksheet (M-K-2-3_Ordering and Comparing Worksheet and KEY)
- number cards 11–20 (M-K-2-1_Number Cards 11-20)

- Observe and grade students as they participate in Lesson 3 activities. 
- One formative assessment tool is the Ordering and Comparing Numbers Worksheet (M-K-2-3_Ordering and Comparing Worksheet and KEY).

Explicit instruction, modeling, scaffolding, and active engagement
W: Explain to the class that they will be counting, identifying, and recognizing numbers during the lesson. These are necessary for mathematicians to be able to add and subtract. We'll use worksheets and games to help with understanding. 
H: The lesson's games and activities will pique students' interest and sustain their zeal. 
E: Using exercises and games, students will compare and order numbers. Gradually increasing levels of responsibility will be required for the games and activities: modeled, shared, guided, and finally independent/partner. 
R: Throughout the class, questions provide students the chance to consider, review, edit, and reevaluate their understanding of mathematics. 
E: Assess students' mathematical comprehension of ordering and comparing numbers by utilizing the Formative Assessment concepts. 
T: The lesson's Extension section includes activities for Small-Group, Routine, and Expansion. 
O: The learning process will progress from modeled to shared to guided, and finally to individual practice. 

"Today, we'll use the terms greater than and less than to compare numbers." Put the text down on the board. "Mathematicians use a symbol for each of these words." On the board, draw each symbol (< and >) next to the corresponding word.

Using base-ten blocks, construct the number 15. Then, using base-ten blocks, construct the number 19. Inform students that the number 15 consists of one ten and five ones. Inform them that 19 has nine ones and one ten. Then say, "The number 19 is greater than 15." "The number 15 is less than the number 19." As you say it, write "19 > 15" and "15 < 19." "I look at how many ones each number has, and I know that 19 is greater than 15 because each number has one ten. The number 19 has more ones than the number 15."

Draw attention to the fact that the less-than and greater-than symbols resemble open mouths. Ask them, "If you were very hungry, would you rather eat 4 cookies or 10 cookies?" Write 4 < 10 and highlight how the symbol resembles a mouth devouring the larger number. Say, "Would you rather have 17 donuts or 2 donuts?" (17) Write 17 > 2, highlighting once more how the symbol resembles a mouth devouring the larger number. Encourage students to use the following technique if they require assistance in recalling the symbols' meanings: The mouth is always drawn to the larger number!

Now let's move on to the numbers:

18 and 12

13 and 17

20 and 11

Ask students to use base-ten blocks to construct both numbers in each pair. After that, ask them to write every number on a whiteboard. Once the numbers have been adjusted to correspond with the various number pairs, ask the following questions:

“How many tens are there in the number 18?” (1)
“How many tens are there in the number 12?” (1)
“How many ones are there in the number 18?” (8)
“How many ones are there in the number 12?” (2)
“Is 12 greater than or less than 18?” (less than)

Have students write the greater-than or less-than symbol between the numbers they wrote on their whiteboard. If students struggle to choose the correct symbol, remind them to think of it like a hungry mouth.

Next, write on the board the numbers 11, 18, and 12. "I can arrange these numbers from greatest to least. Initially, I checked the tens place to accomplish that. 11, 12, 18, and 12 all have one ten. I then count how many ones there are in each number. There are two in 12, eight in 18, and one in 11. Because 18 has the most ones, it is the greatest number. Since 12 contains more ones than 11, it is greater than 11. " Put the numbers on the board in the correct order as you speak.

On the board, write the numbers 13, 19, and 14. On their whiteboards, have students arrange these numbers in ascending order of significance.

Then, repeat the process, but this time, order the results from least to greatest. For the teacher's example, use the numbers 14, 12, and 18, and for the student's example, use the numbers 15, 17, and 13.

Provide students with the M-K-2-3_Ordering and Comparing Worksheet and Key Worksheet on ordering and comparing numbers. As they finish it, keep an eye on them to determine who needs more practice.

Extension:

Routine: Students draw and place two number cards (M-K-2-1_Number Cards 11-20) on their whiteboard. Once the numbers are inserted, students can insert the greater-than or less-than symbol. After drawing three number cards, the students arrange them from either greatest to least or least to greatest.

Small Group: Rehearse the Lesson 3 exercises in a small group setting for students who require more practice.

Expansion: For extra practice and enrichment, use larger numbers and the materials and/or activities found in the links under Related Resources.