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CFISD First Grade MathAddition/Subtraction Within 15

Teacher Notes Page #Unit Title Addition/Subtraction Within 15

Addition (Equal Sign)Addition with 10 framesSubtraction with 10 framesAddition and Subtraction with Number LinesSubtraction- Compare ActionSmartBoard ActivitiesMixed Practice Problems

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9-1112-1314-2425-2627-38

TEKS The student is expected to:1.3B Use objects and pictorial models to solve word problems involving joining, separating, and comparing sets within 20 and unknowns as any one of the terms in the problems such as 2+4=?; 3+?=7; and 5=?-3

1.3E Explain strategies used to solve addition and subtraction problems up to 20 using spoken words, objects, pictorial models, and number sentences.

1.3F Generate and solve problem situations when given a number sentence involving addition or subtraction of numbers within 20.

1.5D Represent word problems involving addition and subtraction of whole numbers up to 20 using concrete and pictorial models and number sentences.

1.5E Understand that the equal sign represents a relationship where expressions on each side of the equal sign represent the same value.

1.5F Determine the unknown whole number in an addition or subtraction equation when the unknown may be any one of the three or four terms in the equation.

Vocabulary Addition, subtraction, joining, separating, comparing, equal, making tens, sum, difference

Tips for Teachers

Essential Understanding:Addition and its inversely related operation, subtraction, are

CFISD 1st Grade TN 14-15 1 Addition/Subtraction Within 15

powerful foundational concepts in mathematics, with applications to many problem situations and connections to many other topics. Addition determines the whole in terms of the parts, and subtraction determines a missing part.

First Grade Teacher NotesAddition/Subtraction Within 15


Addition (Equal Sign)

TEKS:1.5E Understand that the equal sign represents a relationship where expressions on each side of the equal sign represent the same value.

Materials:Anchor chart-The Story of Ten (from Composing and Decomposing Unit)Deck of cards without face cards

Instruction:

Revisit your “Story of Ten” anchor chart from the first lesson in the Composing and Decomposing Numbers to 10 unit.

100 and 10 make 101 and 9 make 102 and 8 make 103 and 7 make 104 and 6 make 105 and 5 make 106 and 4 make 10etc

Use this anchor chart and add on to it to make equations. After you have composed the equations for all the numbers draw connections between the equations that are equivalent. See below:

This is a great way to introduce your students to the commutative property.CFISD 1st Grade TN 14-15 3 Addition/Subtraction Within 15

It is important for your students to understand that the values on both sides of the equal sign are the SAME. Therefore, 0+10=10+0 Read this as “zero plus ten is the same as ten plus zero”.They should also be flexible in the placement of the sum. 0 + 10 = 10 and 10= 0 + 10

Continue with more examples from the chart with addends that equal 10. 3+7=10 and 7+3=10.

Practice:

Group 1: Independent- Place Value Review sheet

Group 2: Partners- Review Tubs

Group 3: Teacher Directed-Teach your students to play the Seven Up Card Game.

You need an ordinary deck of cards. Before beginning, take out the face cards (jacks, queens, and kings). Aces will be used as ones. To play, lay out seven cards face up. The game is played cooperatively, that is, students don't play against each other and there is no winner. Students are looking for pairs of numbers that make ten. If they see one, they show a silent thumb to the chest. The teacher calls on a student and he says the equation and takes the cards. The ten is used by itself, but the students must say 10 + 0 = 10. Replace the cards that were taken with two more from the deck, always leaving seven cards facing up. Continue finding pairs, taking them off, and replacing them. If there are no pairs for ten in the seven cards showing, lay down another seven cards on top of the others. Now when students take off two cards, the cards underneath will be revealed, so you don't need to replace them with new cards.



http://3.bp.blogspot.com/-ggTHITjwC-Q/VEBtAZEhJuI/AAAAAAAAOmI/2qiEL6rkutI/s1600/Seven%2Bon%2BTop.PNG

Addition Using 10 Frames

TEKS:1.3B Use objects and pictorial models to solve word problems involving joining, separating, and comparing sets within 20 and unknowns as any one of the terms in the problems such as 2+4=?; 3+?=7; and 5=?-3

1.3D Apply basic fact strategies to add and subtract within 20, including making 10 and decomposing a number leading to a 10.


Materials: Ten frame for each child2 sided countersAddition 10 frame problems (resource)

Instruction:First graders can solve simple addition and subtraction story problems by counting concrete objects. They establish a one to one correspondence by moving, touching, or pointing to each object that they are counting as they say the corresponding number words. We are NOT using the 4 step to solve these problems

Today we will practice adding. Model the following problem using 2-sided counters.

Max has 2 apples. He picks 5 more. How many apples does Max have now?

Model a variety of counting strategies that might be used to find the number of total counters: Count all: Count each of the counters: 1,2 (pause) 3,4,5,6,7. Count on from the first number: A more efficient way to find the total is to count on,

beginning with the first quantity given in the problem (subitize 2): 2 (pause), 3,4,5,6,7 Count on from the larger number: A still more efficient way to find the total is to count on,

beginning with the larger number (subitize 5) and counting on the smaller number (2): 5, (pause) 6,7.

Ask children to verbalize which strategies they would use!

Mathematicians, let’s try this again:Sara had 2 pieces of candy. She bought 8 more. How many pieces of candy does Sara have now?


Have students use counters to practice different strategies for addition.Have the students Turn and Tell their learning partner what they did to solve the problem.

Boys and Girls, I’m thinking that putting our counters on a ten frame would be even more efficient. Let’s try that.

Discuss with the class how using a 10 frame makes adding easier to visualize.We can represent our counters with the following number sentences:2 + 8 =? 2 + 8 = 10 8 + 2 = 10 10= 2+ 8 2 + 8= 8 + 2

David had 3 baseballs. Sam gave him 9 baseballs. How many baseballs does he have now?(Allow time for the students to use counters to solve this problem)

We can show this problem with the following number sentences:3 + 9 =? 3 + 9 = 12 9 + 3 = 12 3 + 9= 9 + 3

John had 5 pencils. His brother gave him 10 more. How many pencils does he have now?


Use your counters and ten frames to solve this problem. Would it be helpful to use 2 ten frames? Why?5 + 10 =?

Jane has 2 cookies. Her mom gave her some more cookies. Now, Jane has 5 cookies. How many cookies did Jane’s mom give her? (Important: Children should count on from 2, do not subtract)

2 +? = 52 + 3 = 55 = 2 + 3

Alexa has 7 toys. Her dad gave her some more. She has 13 toys now. How many toys did her dad give her?7 +? = 13Practice:

Group 1: Independent- Practice sheet Addition 10 frame problems

Group 2: Partners-Play the “Seven Up” Card game. Have the students write the equations on the table after they choose two cards. For example, 2+8=10

Group 3: Teacher Directed-Teacher will reinforce understanding of the commutative property. Use red and yellow snap cubes to show 1 + 3 = 4 AND 3 + 1 = 4

Lead the students to understand that 1 + 3 = 3 + 1 also. Model this property with several equations, using sums to 15.


First Grade Teacher NotesCFISD 1st Grade TN 14-15 8 Addition/Subtraction Within 15

Addition/Subtraction Within 15

Subtraction Using Ten Frames

TEKS:1.3B Use objects and pictorial models to solve word problems involving joining, separating, and comparing sets within 20 and unknowns as any one of the terms in the problems such as 2+4=?; 3+?=7; and 5=?-3


1.3F Generate and solve problem situations when given a number sentence involving addition or subtraction of numbers within 20.


1.5F Determine the unknown whole number in an addition or subtraction equation when the unknown may be any one of the three or four terms in the equation.

Materials:Magnetic 10 frame or draw a ten frame on your white board10 frames for each student2 sided countersPlace Value review sheet (resource)Addends Game (resource)

Instruction: Mathematicians, we will continue to use our ten frames today. We will use them to solve problems. Let’s solve this problem together:

Ben has 5 cookies. He eats 2 cookies. How many cookies does Ben have left?

Choose a Popsicle stick with a student’s name. Have that student come to the front and show with counters how to solve the problem. Guide the student to separate the counters from the ten frame to show that Ben ate those cookies. Ask if any student had another way to solve. Show the subtraction equation 5 – 2 = 3 which may be used to represent that problem.Discuss why this is a subtraction or separating action and not a joining action.

Wow! Great thinking mathematicians! Let’s solve another problem using subtraction.

Jose had 12 marbles. He gave Angel 4 of them. Now how many marbles does Jose have?

Using a magnetic 10 frame have another student solve this problem with you in front of the class. Have him model separating the counters (marbles) that Jose gave Angel.After students understand the action show them that they can also mark an X on each counter to indicate that it was separated from the group or subtracted from the whole. CFISD 1st Grade TN 14-15 9 Addition/Subtraction Within 15

12 – 4 =?

My family is going to the beach. There are 14 people in my family but my Aunt cannot go.How many people are going to the beach?

Using the ten frame and counters have students solve this problem. Have them mark an X to show that my Aunt cannot go with us. 14 – 1 =?

Your ten frame may look like this:

Practice:


Group 1: Independent- review tubs

Group 2: Partners-Addends Game

Group 3: Teacher Directed-Have the students practice generating and solving subtraction problems with manipulatives in small group. The teacher will give a subtraction equation such as 11- 6 =?The students will think of a word problem using the terms 11 and 6 including the action of taking away or separating from the group.

As the students solve the problems with their counters, the teacher will use a small white board to write the equation for the children to see.



Addition and Subtraction with Number Lines

TEKS:1.3E Explain strategies used to solve addition and subtraction problems up to 20 using spoken words, objects, pictorial models, and number sentences.


Materials:Practice problemsManipulativesNumber Lines Activity Sheet (resource)DominoesNumber of Spots Activity Sheet (resource)

Instruction:

You have introduced the number line to your students in the previous topic. You will now show them how to solve addition and subtraction problems using number lines by counting on and counting back.

This model highlights the measurement aspect of addition and is a distinctly different representation of the operation from the model presented by joining and separating counters. The commutative property is discussed. At the end of the lesson, students are encouraged to predict sums and to answer puzzles involving addition.

Tell the students that they will find sums using the number line model. Then display a large number line and a 5+4 domino, that is, a domino with 5 spots on the left side and 4 spots on the right. Then demonstrate with a counter how a hop of 5 is taken on the number line. Encourage students to count aloud as the hop is made. Then make a hop of 4, starting at the place the counter landed. You might choose to have them record what happened using the equation notation 5 + 4 = 9, or to informally describe the moves this way: “If you take a hop of 5 spaces and then a hop of 4 spaces, you land on 9.” Highlight the fact that in this model, spaces are counted, not points on the number line.


Practice this with several different dominoes with sums to 15.

Tell students that they will now find differences using the number line model. Practice several problems with your students having the frog hop backwards to represent subtraction.

Practice:

Group 1: Independent- Addition and Subtraction equations to 15.

Group 2: Partners- Domino Equations –Number of Spots

Group 3: Teacher Directed- Number Line Activity SheetPut the students in pairs and give each pair some dominoes, a counter, and individual number lines. Students will use the number line activity sheet.

Ask the students to take turns moving the counter on the number line to find the sum shown on the domino and recording the hops in pictures and in equation form. Ask them to draw the first hop and write the first numeral in green and the second hop and numeral in red. Encourage the students to predict the sums and to verify their predictions by moving a counter on the number line.

After allowing time for exploration, ask the students to predict the answers to questions such as “If I take a hop of 3 and then a hop of 5, where will I land?” [8] Now have students make up 2 similar problems on a piece of paper and trade them with a friend. Students should then solve their partners’ problems using the number line. When the pairs have finished, call them together to discuss what they did. Encourage them to use the number line in their explanation. Then ask “If I take a hop of 5 and then a hop of 4, where will I land?" [9] "How about if I take a hop of 4 and then a hop of 5?" [9] "Will this work every time?" [Yes] Encourage them to explore the order property by writing each first addend in green and each second one in red.

Be sure to lead a discussion about the commutative property. You may need to use other examples to illustrate this important property of addition.

As a concluding activity, pose puzzles such as “I am the number you land on when you take a hop of 5 and then a hop of 1. Who am I?” [6] CFISD 1st Grade TN 14-15 13 Addition/Subtraction Within 15


Subtraction- Compare Action

TEKS:1.3E Explain strategies used to solve addition and subtraction problems up to 20 using spoken words, objects, pictorial models, and number sentences.


Materials:Practice problemsManipulatives Addition/Subtraction with Number lines Practice Sheet (resource)

Instruction:

Cole and Jeff went to the zoo.

Cole saw 6 elephants.

Jeff saw 8 zebras.

How many more animals did Jeff see than Cole?

Begin the “Four-Step Problem Solving” with the students.

Have students find the question and identify the important words. Ask students to write the main idea for step 1.

“What are we trying to find?” “What are the most important words in the question?”


In step 2, re-read the problem and identify the “who” and “what” and use unifix cubes to build the model. Using different colors of unifix cubes for each person in the story will visually help students see the problem. Note that the “who” and “what” are written as they come in the story.


More animals J than C

C elephant

J zebra


Begin by rereading the story one sentence at a time. Adjust the model one sentence at a time. This is important so that students understand how the sentence changes the model drawing.

Cole and Jeff went to the zoo. (No change)

Cole saw 6 elephants. Adjust the model with unifix cubes and then do the model drawing. Questions to ask are:

Do we need to adjust the model? Why? How do we know how to adjust the model? What do we need to label?


C elephant

J zebra

6More animals J than C

Jeff saw 8 zebras. Adjust the model with unifix cubes and then do the model drawing. Questions to ask are:

Do we need to adjust the model? Why? Which model do we adjust? Why? How do we know how to adjust the model? What do we need to label?

How many more animals did Jeff see than Cole? Adjust the model with unifix cubes and then do the model drawing. Questions to ask are:

Do we need to adjust or label the model? Why? How do we know how to adjust or label the model? Where is the “more” that Jeff saw?


6

8

C elephant

J zebra


?

6

8

C elephant

J zebra


Use the model to help students see the action of comparing and that the number sentence will be subtraction. Emphasize which number will be first in the subtraction fact. Show the number sentence in step 3.

6

8

In step 4, describe how the problem was solved—what strategy was used in step 3? This step is important to building academic language. Words that can be included in the how are subtract, difference, compare.

6

8

5. Repeat the process modeling several problems. If your students need more practice there is a SmartBoard activity included at the end of these Teacher Notes.


8- 6 2

8- 6 2

8-6=2

8-6=2

8- 6 2

C elephant

J zebra


Found the difference ORSubtracted 6 from 8 ORCompared 6 to 8 OR

C elephant

J zebra


Practice:

Group 1: Independent- Addition/Subtraction with Number lines Practice Sheet

Group 2: Use domino cards, real dominoes, or dice to practice adding 2 numbers

Group 3: Small Group Instruction-Work through a 4-step problem from the sample problems.


SAMPLE PROBLEMS:

1. Cole and Jeff went to the zoo.

Cole saw 6 elephants.

Jeff saw 8 zebras.

How many more animals did Jeff see than Cole?

2. Jay has 4 white dogs and 3 brown dogs.


How many more white dogs than brown dogs

does Jay have?

3. Nine chicks hatched at Farney Elementary. Two


chicks hatched at Robison Elementary. How many

more chicks hatched at Farney than

Robison?

4. The fish tank at Francone has 9 fish.

It also has 5 crabs.


How many more fish than crabs are in the

fish tank?

5. Four turtles were sleeping in the sun.

Twelve turtles were swimming in the water.


How many more turtles were swimming than

sleeping?

Smartboard ActivitiesAddition/Subtraction Within 15

Smartboard Activities

Materials:SmartBoard activities

Instruction:Read the problem with the students to find the keywords. Circle the important words in the question.

Reread the problem again to find the who/what. Write the who/what for the problem following the four step process.


Label J for Joe and N for Nick on step 2. Use the clone to create a picture that represents the number given in the problem. To clone, right click and select clone on the picture located on the upper right hand corner and drag to the desired location.

Draw a line between Joe and Nick’s baskets to show the comparing action.

Write a number sentence to show the comparing action in step 3.

Describe how you solved the problem in step 4.

PracticeComplete additional slides for practice with small groups.


Mixed Practice

Put Together, Take Away, Compare

Eleven butterflies

are on a flower.

Seven butterflies fly

away.


How many butterflies are still on the flower?

Fourteen penguins are playing on the ice.

Six penguins are in the water.

How many more penguins are on the ice than in the

water?


. The pet shop had 15 birds.

The shop sold 8 of the birds.

How many birds are still in the pet store?


Maria has 5 cubes.

Ben has 6 cubes.

How many cubes do Maria and Ben have?


Sue saw 4 beach balls on the beach.

Chris saw 6 beach balls on the beach.

Which number sentence shows how many beach balls

Chris and Sue saw?

A. 4 + 6 = 10

B. 4 + 8 = 12

C. 8 – 4 = 4


May saw 5 birds.

Linny saw 9 birds.

Which number sentence can be used to find how many

more birds Linny saw than May?

A. 9 + 5 =14

B. 9 – 5 =4

C. 9 - 3 =6


Five birds were on top of the fence.

Two birds flew away.

What number sentence can be used to find how many

birds are on the fence now?

A. 5-3=2

B. 5-2=3

C. 6-5=1


Ms. Jones has 11 boys and 7 girls in her class.

What number sentence can be used to find how many

more boys than girls are in the class?

A. 11 + 3 = 14B. 11 – 7 = 4C. 12 – 7= 5

There were 14 girls and 9 boys by the swings at recess.


What number sentence can be used to find how many fewer

boys than girls were by the swings?

A. 14 + 9 = 23

B. 5 + 9 = 14

C. 14 – 9 = 5

Ms. Malone has 6 boys in her class.

Ms. Sun has 8 boys in her class.

What number sentence can be used to find how many boys


are in both classes?

A. 6 + 8 =14

B. 10+4 =14

C. 8 – 6 =2

The pet shop has 5 dogs, 6 cats and 9 fish.


How many fewer cats than fish?

A. 9 – 6 = 3

B. 9 – 5 = 4

C. 9 + 5 = 14

Josh has 3 pencils, 2 highlighters and 9 crayons

in his desk. How many fewer highlighters than crayons does CFISD 1st Grade TN 14-15 36 Addition/Subtraction Within 15

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http://images.google.com/imgres?imgurl=http://www.clipartpal.com/_thumbs/pd/education/crayon_black.png&imgrefurl=http://www.clipartpal.com/clipart_pd/education/crayon1.html&usg=__Gv-x_9-nRzqsmG8QGBOh8rKy82Q=&h=272&w=357&sz=23&hl=en&start=4&zoom=1&tbnid=n5G6OCiY91r7aM:&tbnh=92&tbnw=121&ei=zRqXTq2GAo2FsgLipcjcBA&prev=/images%3Fq%3Dcrayons%2Bclipart%2Bblack%2Band%2Bwhite%26hl%3Den%26gbv%3D2%26tbm%3Disch&itbs=1

Josh have?

A. 3 + 2 = 5

B. 9 – 2 = 7

C. 9 + 3 = 12


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