1

Second Grade

Parent Math Information

Information gathered by 2nd Grade Teachers

(all trained Cognitively Guided Instruction teachers)

Common Core National Math

Standards (College and Career Readiness Standards)

v

2010 Arizona Math Standards

v

Kyrene Math Standards

2

http://www.azed.gov/azcommoncore/families/

Your child is learning:

Times have changed…

Today’s students must master

advanced skills in mathematics,

science, and technology to stay on

track for college and for promising

careers. Mathematics teaches ways

of thinking that are essential to

work and civic life.

3

*Students who take algebra and geometry go on to college at

much higher rates than those who do not (83% vs. 36%).

*Most four-year colleges require three to four years each of

high school math and science for admission.

*Almost 90% of all new jobs require math skills beyond the

high school level

4

Second Grade- Five Domains

Operations and Algebraic Thinking

Numbers in Base Ten

Geometry

Measurement and Data

Mathematical Practices

5

Mathematical Practices 1. Make sense of problems and persevere in solving them.

2. Reason abstractly and quantitatively.

3. Construct viable arguments and critique the reasoning of

others.

4. Model with mathematics.

5. Use appropriate tools strategically.

6. Attend to precision.

7. Look for and make use of structure.

8. Look for and express regularity in repeated reasoning.

We teach problem solving to help improve:

6

Your child using mathematical procedures in the classroom…

7

Your child using mathematical procedures in the classroom…

8

Common Addition and Subtraction Situations Result Unknown Change Unknown Start Unknown

Add to

Two bunnies sat on the

grass. Three more bunnies

hopped there. How many bunnies are on the grass now?

2 + 3 = ?

Two bunnies were sitting

on the grass. Some more bunnies hopped there.

Then there were five bunnies. How many bunnies hopped over to

the first two? 2 + ? = 5

Some bunnies were sitting

on the grass. Three more bunnies hopped there.

Then there were five bunnies. How many bunnies were on the grass

before? ? + 3 = 5

Taken from

Five apples were on the table. I ate two apples.

How many apples are on the table now? 5 – 2 = ?

Five apples were on the table. I ate some apples.

Then there were three apples. How many apples did

I eat? 5 – ? = 3

Some apples were on the table. I ate two apples.

Then there were three apples. How many apples were on the table before?

? – 2 = 3

Put

Together/ Take Apart2

Total Unknown Addend Unknown Both Addends Unknown1

Three red apples and two green apples are on the table. How many

apples are on the table? 3 + 2 = ?

Five apples are on the table. Three are red and the

rest are green. How many apples are green?

3 + ? = 5, 5 – 3 = ?

Grandma has five flowers. How many can she put in her red vase and how

many in her blue vase? 5 = 0 + 5, 5 = 5 + 0

5 = 1 + 4, 5 = 4 + 1 5 = 2 + 3, 5 = 3 + 2

Compare3

Difference Unknown Bigger Unknown Smaller Unknown

(“How many more?”

version): Lucy has two apples.

Julie has five apples. How many more apples does Julie have than

Lucy?

(“How many fewer?” version): Lucy has two apples.

Julie has five apples. How many fewer apples

does Lucy have than Julie? 2 + ? = 5, 5 – 2 = ?

(Version with “more”):

Julie has three more apples than Lucy. Lucy

has two apples. How many apples does Julie have?

(Version with “fewer”):

Lucy has 3 fewer apples than Julie. Lucy has two apples.

How many apples does Julie have?

2 + 3 = ?, 3 + 2 = ?

(Version with “more”):

Julie has three more apples than Lucy. Julie has five

apples. How many apples does Lucy have?

(Version with “fewer”): Lucy has 3 fewer apples

than Julie. Julie has five apples. How many apples does

Lucy have? 5 – 3 = ?, ? + 3 = 5

Your child is

expected to

know how

to solve 12

different

types of

problems.

Operations and Algebraic Thinking

Mental Math Strategies through 20

*Plus 0 9+0=9

*Counting On/Counting Back

7+2~ 7, 8, 9; 12-3~ 12, 11, 10, 9

*Counting Up to Subtract

14-9~ 9… 10,11,12,13,14…answer is 5

*Doubles 7+7= 14 ~ Doubles Plus 1 7+8= 7+7+1

*Commutative Property 9+6= 6+9 9+6=15 so 6+9=15

*Relationship Between Addition and Subtraction 8+4=12 so 12-8+4

*Making 10 8+6= 8+2+4= 10+4= 14

*Decomposing a Number Leading to a Ten

13-4= 13-3-1= 10-1=9

9

Your child needs to memorize basic facts.

Lucy had 39 stickers and her mom gave her 24 more

stickers. How many stickers does Lucy have now?

(Solve and show your work)

10

. Traditional Algorithm is not taught until 3rd grade

Here are some common mistakes that students make,

and that test-makers take advantage of…

29 + 14

1

29 29 29

+14 +14 +14

43 313 16

(correct) (incorrect- failed to “carry the “one”

or added all the numbers together)

11

Direct Modeling

12

Base 10

13

100’s Chart

14

Open Number Lines

15

Number Strings

(Decomposing)

16

Adding in Chunks

(Incrementing)

17

Compensation

18

Subtraction

Lucy had 54 stickers and she gave her mom 29 of

them. How many stickers does Lucy have now?

*Students will often use related addition strategies when

solving subtraction strategies (29 + __ = 54)

19

common mistakes… 34-19= __

20

2 14

34 34

-19 -19

15 25

(correct) (incorrect- subtracted from the

bottom up in the ones place)

Direct Model

21

Base 10

22

Hundreds Chart

23

Open Number Line

24

Number Strings

(Decomposing) (leaving first number whole, decomposing second number)

25

Incrementing

26

Compensating

27

Sample 2nd grade test

question…

In the question, “There were 67 boys ad 54 girls

on the playground. How many kids were on the

playground?” a second grade student started

with 60 + 50 =110. What will they do next?

a. 60 + 4 c. 7 + 4= 11

b. 60 + 11 d. 50 + 7

28

Another Second grade

sample question…

29

Sample 3rd grade test

question…

Fill in the blanks below with whole numbers greater than 1 that will make

the number sentences true.

1. 63 ÷ ___ = 7

2. 63 = 21 × ___

3. 21 = ___ × 7

4. 7 × (___ × ___ ) = 21 × 7

5. (21 × 3) ÷ ___ = 7

Part B: If the product of two whole numbers greater than 1 is 63, what

could the two whole numbers be? _______, ________

30

Helping Your Child at Home

RELAX! Be Patient

*You are a “guide” - don’t take over for your child

*Believe that your child can be successful

*Expect your child to work hard to learn mathematics

*Always show all your work- have your child explain the problem

and his thinking out loud

*Talk about why solutions are correct and incorrect

*Help your child connect math with daily life

*Be supportive of methods your child shares from school

31

(feel free to e-mail your child’s teacher if you

have any questions)

32

Thank you for reading!!