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## Focus on Two

Pre-K-2
1

A nursery rhyme provides a context for using the number 2. Students make groups of two, write the numeral 2, and record a group of two on a personal recording chart.

Begin the lesson by teaching the students to sing or chant the song "Catching a Fish", as found on the Nursery Rhymes and Songs Resource Sheet.

Because many students come to school able to count at least a few numbers by rote, this song is an excellent starting point for number work. Note: Rote counting is the naming of the number words in the correct sequence. Rational counting is assigning one and only one number name to each object in a group. One way to foster rational counting is to use counting books. Because such books gently pave the way for more formal rational counting experiences, you may want to collect several counting books to display throughout the unit in your class library.

Next, recite the nursery rhyme "Jack and Jill." Tell the students they will act out the rhyme. Ask, "How many children will I need to call to the front of the room?" Then call on a boy and a girl and have them act out the rhyme. The students can march to simulate going up the hill and turn around twice to depict "tumbling down." Repeat with other pairs of students.

Have the students sit down in a central place, such as a carpet. Then show the students the numeral 2, as found on the Numeral Cards.

Say, "Lift your hands in the air. How many hands are you holding up?" Prompt the students to answer "Two." [They will be using the cardinal form of number as they answer. A cardinal number is a number that answers the question "How many?"]

Display a large set of counters (such as Lima beans), and ask the students to come up and take one counter in each hand. When all the students have returned to their seats, ask them to count aloud the counters they are holding. Model this with two counters that you are holding, saying, "One, two." Then ask," How many counters are you holding?" Encourage the students to answer "Two."

Now drop your two counters into a metal bowl [so they will be heard as they drop]. Count "One, two" as you drop the counters. Then have the students come up one at a time and drop the counters into the container, saying "One, two" as they drop them. You might invite the class to count along as each child drops his or her counters into the bowl.

Now ask the students to look at the numeral 2 that you have displayed. Tell them that this figure means "two" and that they will be learning to write it. Turn your back to the students [so you will be writing in the same orientation as will the students] and trace the figure in the air, using large strokes. Encourage the students to do it with you using very large movements. You may wish to sing the actions you use to make the numeral. Lyrics to use when making the numerals up through 5, along with other suggestions for practice in writing the numerals, can be found on the Suggestions for Numeral Writing Practice Resource Sheet.

Next, show the students a box cover or pan in which you have placed some rice or play sand. Put the numeral card with "2" written on it next to the container. Now say "Watch me as I draw a '2' in the sand tray." Encourage several other students to try this. [Throughout this unit, each new numeral should be written in this way and the sand (or rice) tray should be available for additional practice.]

Now distribute copies of the Show How Many Activity Sheet.

Have those students who can write put their name at the top. When they are ready, ask them to put a finger on the column with a "2" at the top. Then ask them to color in 2 boxes in that column, starting at the bottom row.

Demonstrate this, and circulate as they work, encouraging them to count aloud as they color the boxes. Then collect the charts or tell the students to put the chart where it will be available for the next six lessons.

Assessment Options

1. The Questions for Students will help you assess the students' level of knowledge.
2. You can use the Class Notes recording sheet to document what you discover about the students' understanding and skills. You may find these records useful when discussing the students' progress toward learning targets with students, and with administrators, colleagues, and parents or caregivers.

Extensions

1. Throughout this unit, students may also use the Five Frame Tool to explore numbers up to 5.
Five Frame Tool
2. Move on to the next lesson, Three in a Set.

Questions for Students

1. What number did we talk about today? Can you show me that many fingers?

[Two; students should be able to hold up two fingers.]

2. Can you count from one to our target number for the day? Show me the number of objects that equal our target number for today.

3. Can you write that number?

[Students should be able to write the numeral 2.]

4. How did you show that number on your chart? Did everyone show it the same way?

[Possible answers: I colored two boxes red; I colored two boxes blue; I made two boxes purple.]

5. Where on the chart is the number that shows how many fingers I am holding up? (Hold up two fingers.)

6. Can you point to the number as you say it?

7. Listen as I ring this bell (or tap this drum or hit this triangle). How many sounds did you hear?

[Two.]

8. Can you see the number 2 anywhere in the room?

[Possible answers include on the clock, on the board, or on my paper.]

Teacher Reflection

• Which students could count by rote to five? What experiences are necessary for those who could not?
• Which students are able to count rationally to two?
• Which students were able to identify the numeral 2? Which could write it?
• Which students were not able to identify how many times you rang the bell? What instructional experiences do they need next?
• What adjustments will I make the next time that I teach this lesson?

### Three in a Set

Pre-K-2
In this lesson, students construct sets of three, compare them with sets of two, and write the numeral 3. They also show a set of three on their recording chart.

### One, Two, Three--Go

Pre-K-2
After reviewing the numbers 2 and 3, students construct and identify sets of one. They compare sets of one, two, and three objects and record a set of three in chart form.

### Finding Four

Pre-K-2
Students explore the number 4. They make sets of four, write the numeral 4, and compare sets of four to sets of one, two, and three.

### Here's a Handful

Pre-K-2
Students construct sets of up to five items, write the numeral 5, identify sets of five, and record "5" on a chart. They also play a game that requires recognizing the numerals to 5. This lesson provides opportunities for connecting mathematics with music.

### Zero Our Hero

Pre-K-2
Students explore sets of zero items and practice writing the numbers 0 through 5. Students count back from five, identify sets of up to five items, and record "0" on a chart. They also construct sets of up to five items.

### Learning Objectives

Students will:
• Construct groups of two objects.
• Identify and write the numeral 2.
• Record a group of two on a graph.

### NCTM Standards and Expectations

• Count with understanding and recognize "how many" in sets of objects.
• Develop a sense of whole numbers and represent and use them in flexible ways, including relating, composing, and decomposing numbers.
• Develop understanding of the relative position and magnitude of whole numbers and of ordinal and cardinal numbers and their connections.
• Use multiple models to develop initial understandings of place value and the base-ten number system

### Common Core State Standards – Mathematics

-Kindergarten, Counting & Cardinality

• CCSS.Math.Content.K.CC.A.3
Write numbers from 0 to 20. Represent a number of objects with a written numeral 0-20 (with 0 representing a count of no objects).

-Kindergarten, Counting & Cardinality

• CCSS.Math.Content.K.CC.C.6
Identify whether the number of objects in one group is greater than, less than, or equal to the number of objects in another group, e.g., by using matching and counting strategies.

-Kindergarten, Counting & Cardinality

• CCSS.Math.Content.K.CC.C.7
Compare two numbers between 1 and 10 presented as written numerals.

-Kindergarten, Algebraic Thinking

• CCSS.Math.Content.K.OA.A.3
Decompose numbers less than or equal to 10 into pairs in more than one way, e.g., by using objects or drawings, and record each decomposition by a drawing or equation (e.g., 5 = 2 + 3 and 5 = 4 + 1).

-Kindergarten, Algebraic Thinking

• CCSS.Math.Content.K.OA.A.4
For any number from 1 to 9, find the number that makes 10 when added to the given number, e.g., by using objects or drawings, and record the answer with a drawing or equation.

-Kindergarten, Number & Operations

• CCSS.Math.Content.K.NBT.A.1
Compose and decompose numbers from 11 to 19 into ten ones and some further ones, e.g., by using objects or drawings, and record each composition or decomposition by a drawing or equation (such as 18 = 10 + 8); understand that these numbers are composed of ten ones and one, two, three, four, five, six, seven, eight, or nine ones.

• CCSS.Math.Content.1.NBT.B.3
Compare two two-digit numbers based on meanings of the tens and ones digits, recording the results of comparisons with the symbols >, =, and <.