Extra
What is one strategy you can use to decide if a number is an even number?
1. See if the objects can be separated into two equal groups
2. See if the number ends in 0, 2, 4, 6, 8
3. See if objects can be paired with out any left over
Coach Alex wanted to create 2 groups of his 16 players. Is 16 an even or odd number?
Even; Answers will vary.
Skip count by 2's.
2, 4, 6, 8, ___, ___, ___, ____
10, 12, 14, 16
What is the repeated addition equation for the array below?
&&&&&
&&&&&
5 + 5 = 10
OR
2 + 2 + 2 + 2 + 2 = 10
Is the number even or odd?
9
Use pictures, numbers, or words to prove your answer.
Odd - answers may vary
What is a strategy you can use to decide if a number is an odd number?
1. See if the object can separate into two equal groups with two equal addends (ex: 2 + 2). If not, the number is odd.
2. See if objects can be paired - if there are any left over, the numbers odd.
3. Does the number end in 1, 3, 5, 7, 9
Cierra has 3 rows of books. Each row has 5 books. How many books does Cierra have? Use pictures, numbers, or words.
3 + 3 + 3 + 3 + 3 = 15
or
5 + 5 + 5 = 15
Skip count by 3's. What are the missing numbers?
3, 6, 9, 12, 12, ___,___,___
15, 18, 21
What is the repeated addition equation for the array below?
#####
#####
#####
5 + 5 + 5 = 15
OR
3 + 3 + 3 + 3 + 3 = 15
Is the number even or odd?
10
Use pictures, numbers, or words to prove your answer.
Even - answers may vary
Give 2 examples of arrays you see around the classroom.
Answers may vary
Ms. Honey wanted to arrange the desks into 4 rows of 5. If she has 22 students, will she have enough desks? Use pictures, numbers, or words.
She will not have enough because 4 rows of 5 makes only 20 total.
Skip Count by 4's. What are the missing numbers?
4, 8, 12, ____, 20, ____, 28
16, 24
What is the number sentence for this array?
&&
&&
&&
&&
4 + 4 = 8 or 2 + 2 + 2 + 2 =8
Is the number even or odd?
19
Use pictures, numbers, or words to prove your answer.
Odd - answers may vary
Does this addition equation match the array below?
7 + 2 = 9
x x x
x x x
x x x
No - 3 + 3 + 3 = 9 matches the array
Julian has 12 toy cars. What are TWO different ways he could create an array with his toy cars?
Show on your write board AND write a repeated addition sentence/equation that matches.
Arrays will vary
What is the pattern?
5, 10, 15, 20
Skip counting by 5
What is the number sentence for this array?
@@
@@
@@
@@
4 + 4 = 8
OR
2 + 2 + 2 + 2 = 8
Ava said the number 14 is even because if she paired 14 objects, there are none left over.
Jordan said 14 is even because he could separate 14 items into two equal groups with 7 items in each group.
Who is correct?
Who is correct?
They are both correct because you could use either strategy to figure out if a number is even.
Which repeated addition equations match the array below:
$ $ $ $
$ $ $ $
$ $ $ $
a. 3 + 3 + 3 = 12
b. 4 + 4 + 4 = 12
c. 11 + 1 = 12
b
A 2nd Grade arranged their cups into an array. If there are 24 students in the class, how could they have arranged the cups? Draw the array and write the repeated addition for your array.
Answers may vary
How does skip counting help us understand arrays?
Instead of counting by 1s, we can skip count by the number in each row or column.
What is the repeated addition equation for this array?
XXXX
XXXX
XXXX
XXXX
4 + 4 + 4 + 4 = 16
Coach Annie wanted her 17 girls to play tug of war. Is 17 odd or even? Prove your answer with pictures, numbers, or words.
Odd - answers will vary