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This is a powerpoint presentation• To activate this slide show On a PC:
- Click on the tab entitled “Slide Show”. Then click the first icon called “From Beginning”.
On a MAC:- Click on the tab across the top entitled “Slide
Show”. When the drop down menu appears, click the first link called “From Start”.
* This powerpoint presentation is animated and will only function correctly using Microsoft Office Powerpoint Software.
Making Connections Through the Grades in Mathematics
A glimpse into thinking flexibly about numbers in the elementary grades and how it supports later
work in algebra.
Math fact expectations by end-of-grade level
Grade K - Add and subtract within 5 with accuracy and speed
Grade 1 - Add and subtract within 20 with accuracy and speed
Grade 2 - Add and subtract within 20 to compute with multi-digit numbers
Grade 3 - Add and subtract within 20 and multiply and divide within 100 with accuracy and speed
Grade 4 - Add and subtract within 20 and multiply and divide within 100 to compute with multi-digit whole numbers using efficient strategies.
Grade 5 - Use knowledge of basic facts to compute with fractions and decimals using efficient strategies.
Children come to school with a wealth of mathematical knowledge
When we receive children in preschool and kindergarten, children already use patterns and
relationships as they develop their mathematical understanding of the world around them. We build
on this by strategically selecting problems and numbers that develop big ideas in mathematics
throughout the grade level continuum.
We begin by understanding number.
You will have two seconds before they disappear.
I will flash dots on the screen. Your task is to figure out how many there are.
How many did you see?
You will have two seconds before they disappear.
I will flash dots on the screen. Your task is to figure out how many there are.
How many did you see?
Early Number Development
It is important for young children to not only count in the counting sequence, 1, 2, 3, 4, 5,…, but also comprehend that a number (symbol) represents a quantity.
This is a huge developmental milestone that takes time to develop.
Building Automaticity
It is also a big developmental idea for children to understand that numbers also contain other numbers. Meaning, a “5” contains the quantity “4” and that five is actually composed of a 4 and a 1 or a 3 and a 2…
It is important to push students beyond counting strategies to recognize numbers as being
composed of other numbers and that numbers can be decomposed into other numbers.
We look for patterns and make use of structure to make sense of and
organize our thinking.
Concrete and pictorial models help us to visualize.
Building Numbers Using the Ten-Frame?
You will see dots in the ten-frame for 2 seconds.
Can you tell how many there are?
Building a foundational understanding and making connections
Example:When students understand the commutative property of addition, learning the basic facts is easier.If a child is working on addition with 8 knows that 5 + 3 = 3 + 5, she/he can generalize and cut the number of facts to memorization in half.
Composing and Decomposing Numbers
Composing and decomposing numbers is related but different than adding and subtracting.
We build on big ideas that are foundational for grades 1 an 2
• Counting• Composing and Decomposing numbers• Equivalence• Cardinality – understanding that the last
number said tells, “How many?”• Conservation of Number – understanding that
no matter how the objects are arranged the quantity remains the same.
Using the five-structure to help think about addition
Solve.
5 + 815 + 825 + 8135 + 8135 + 18
Some children in 1st or 2nd grade might think 5 + 5 + 3 , then
( )
What strategy did you use?
10 + 3 = 13
The associative property of addition
How can this idea help you solve these problems?
Children use their knowledge of decomposing numbers to find equivalent representations to make problem solving easier.
Children in early grades may use strategies to organize and make
sense of numbers like…
Use knowledge of 6 + 6 to help solve related problems like 6 + 7.
• Doubles Plus 1 • 6 + 7 = 6 + 6 + 1 or
• Doubles Minus 1• 7 + 7 - 1 = 13
( )
( )
Children in early grades may use other strategies like…
• Using compensation
6 + 8 =
• Using known facts ( landmarks, friendly, familiar numbers)
6 + 8 = 14 so 7 + 8 must be 14 + 1 = 15
7 + 7 = 14
Addition Procedure with Regrouping
26
811 group of 10+ 55
1 Put down the 1 and carry the 1
7 tens plus 1 ten is 8 tens or 80.
1
Another Way to Record the Same Thinking for Regrouping
26
11+ 55
Or decompose the numbers and start with the tens
+ 7081
(20 + 6)+ (50 + 5) (70 + 11)
Partial Sums
In the intermediate grades students continue to build their algebraic
reasoning as it applies to multiplication, division and fractions.
MULTIPLICATIONOr, use a numerical representation
to illustrate this partial product strategy
8
8 x 15(10+ 5)
80 40
80 + 40 = 120
Decompose 15 into
ten and ones
(8 x 10) + (8 x 5)
Also known as th
e distributive
property of m
ultiplication over
addition
• Physical or concrete models, i.e. using manipulatives, coins, students acting it out,…
• Drawing models to visualize, i.e. using open number lines, arrays, coin images,…
• Numeric models: i.e. using the standard algorithm, algebraic properties,…
Models to Represent Your Thinking
MULTIPLICATIONUse the Open Array Model
to Illustrate this Partial Product Strategy
6
6 x 2920+ 9
120 54
120 + 54 = 174
Decompose 29 into
tens and ones
Fairfield Public Schools 2011-2012
Division
How would you divide
174 ÷ 6 = ?
Solve it mentally and think about how you approached the problem.
Fairfield Public Schools 2011-2012
How would you record your thinking?
2
-12 5
4
54
96 goes into 17 twice.Put down the 12 and
subtract from 17 to
get 5.Bring down the 4 to
make 54. 6 goes into
54 nine times.Digit
Oriented
Fairfield Public Schools 2013-2014
Or you could record your thinking?
20
-120 54
+ 96 goes into 174
twenty times.Put down the 120 and
subtract from 174 to
get 54.6 goes into 54 nine
times.Number
Oriented
Or record your thinking?
20-120 54
+ 9
6 goes into 174 twenty times.Put down the 120 and
subtract from 174 to
get 54.6 goes into 54 nine
times.Number
Oriented 29
174 ÷ 6 =
This division problem was solved the same way, using place value
concepts each time. The difference is how it is recorded.
Try this…
There is a sale on gift wrap for $2.98 a roll with a limit of 3 rolls. How much would it cost for three rolls?
Turn and Talk
How did you find your answer?
• Did you solve it using paper & pencil?
• Did you solve it with a calculator (or on your phone?)
• Did you solve it mentally?
• Did anyone decompose $2.98 into ($2.00 + .98)?
• Did anyone think of an equivalent value ($3.00 - .02)?
What strategy did you use?
• Did you use the standard algorithm?
2.98x 3
4
2
9 08 08 9 4
2
0+
OR,
Did you use a different strategy?
Did anyone decompose 2.98 and use partial products?
$2.98 x 3 can be thought of as …
2 cents less than $3.00Or ($3.00 - .02)
3 rolls at $3.00 is $9.00Then subtract (3 x 2 cents = 6 cents)
$9.00 subtract 6 cents is $8.94
Recording that thinking mathematically
3 x (3.00 - .02)
(3 x 3.00) – (3 x .02) = 9.00 – .06 = $8.94
Distributive property of multiplication over subtraction
Why is it important to use different strategies? (Turn & Talk)
• There is more than one way to solve a problem.
• Some ways are more efficient than others.
• Children may think differently than you about how to solve a problem.
• It is important to validate that thinking. Knowing their thinking will also help you when providing support.
FractionsComparing unit fractions
Which is bigger or ?
A common misconception children have is to think that 4 is bigger than 2 therefore is bigger than
Making the Link to Algebra 12 x 12 = (10 + 2) (10 + 2)
(10 x 10) + (2 x 10) + (10 x 2) + (2 x 2) =
10
10 2
2
+
+
(10 x 10)
(2 x 2)
(10 x 2)
(2 x 10)
100 + 20 + 20 + 4
A pictorial model
• Teachers, Principal and Math Science Teacher
• FPS website – Curriculum – Math • Parent Letters• Basic Facts practice• Homework –Teachers differentiate
homework based on student needs
• http://fairfieldpublicschoolsk5math.wikispaces.com/home
Parent Resources: