Grade 4
Tips for Helping at Home
Questions to ask:
•
What is it that you don’t understand (have your child
be
specific)?
•
What about putting things in order?
•
Could you try it with simpler numbers?
•
Can you guess and check?
•
Does this make sense?
•
What can you do to explain your answer to show oth-
ers what you are thinking?
•
Does your answer seem reasonable?
When you and your child are buying
something, figure out together what
the change will be. If you buy an item
that costs $3.89 and give the clerk
$5.00, figure out how much you should get back.
If you drive, show your child the odometer on your car and
ask them to help you figure out how far it is to the grocery
store or the playing field; if you start at 24,532.1 miles and
when you get there the odometer reads 24,533.8, how far
have you gone?
Another way children can get
experience working with decimals is by walking, running, or
riding their bikes on routes where they know the distances.
Help your child figure out how far it is to different places in
your neighborhood. If there are any fun runs, bike rides, or
walks for charities in your community, try to get involved in
them. Many of these events involve distances with decimal
amounts like 3.1 or 6.2 miles. These are excellent opportu-
nities for children to get fit, to contribute to their community,
and of course to become better mathematicians.!
Mathematical Emphasis
I
nvestigation 1—Everyday Uses of Money
•
Exploring number relationships in the context of money
•
Developing Strategies for combining numbers, particularly
money amounts
•
Using Landmark numbers to compare and find differences
between two quantities
•
Using standard addition and subtraction notation to record
combining and comparing situations
•
Using the calculator to solve problems
•
Interpreting decimals on the calculator as amounts of
money
Investigation 2—How Far? Measuring in Miles and
Tenths
•
Estimating Local distances in miles and tenths of miles;
developing a sense of approximate length of a mile and
1/10 of a mile
•
Comparing and combining decimal numbers and finding
differences between these numbers
•
Seeing the relationships of decimal part to the whole
•
Measuring distances on maps using a scale
•
Becoming familiar with common decimals and fraction
equivalents
•
Estimating and calculating sums of quantities that include
decimal portions
Investigation 3—Calculating Longer Distances
•
Measuring distances on maps using a scale
•
Comparing and combining numbers in the hundreds and
thousands
•
Using standard addition and subtraction notation to record
combining and comparing problems
Websites
•
http://www.aaamath.com/add.html
(addition practice)
•
http://www.gameslib.com/games/1477
(subtraction action)
Addition and Subtraction
0 0 2 4 5 3 2 .1
Keeping Track of Addition and Subtraction
A good addition strategy, when you are adding large num-
bers using metal math is to jot down steps so you don’t
lose track of your procedure: For example, suppose you
are adding the four numbers below. You might want to jot
down the partial sums like this as you add from left to right:
Now you can easily
add the partial sums in
your head and write
down the results.
Jotting down steps -
helps students remem-
ber their approaches and helps them explain how they
arrived at an answer.
As an example,
Karen is adding up
several prices,
Here is what she
might think and
write:
A good strategy to
use for comparing
numbers or sub-
traction is to use a number line notation. For example, sup-
pose the class is comparing right and left handfuls of
beans: “I have 84 beans in my right hand and 142 in my
left. How many more could I hold in my left hand?” A stu-
dent could write:
Adding up
the sums
of the
“jumps”
between
84 and 142
gives the student the difference (answer to the subtraction
problem) between the two numbers.
Mental math
activities are exercises in number sense,
providing students the opportunity to solve problems using
different strategies, which enhances the understanding of
number.
When given a mental
math problem: 1000 -
638 = ?
Here is an example
of how a student
might solve it.
By “taking notes” the student is able to solve the problem
successfully.
Economopoulos, K. Investigations in Number, Data, and Space: Money,
Miles and Large Numbers. Dale Seymour, 1998.
Vocabulary
estimate:
to calculate approximately the
amount of or value of something mentally.
multiple:
a number that can be divided by
another number without remainders; the multi-
ples of 10 are 1, 2, 5, and 10.
sum:
an amount obtained as a result of add-
ing numbers.
difference:
the amount that remains after one
quantity is subtracted from another.
decimal:
A linear array of digits that repre-
sents a real number, every decimal place indi-
cating a multiple of a negative power of 10.
For example, the decimal 0.1 =
1
/
10
, 0.12 =
12
/
100
, 0.003 =
3
/
1000.
negative integers:
A member of the set of
negative whole numbers {-1, -2, -3, . . . }, and
zero {0}.
positive integers:
A member of the set of
positive whole numbers {1, 2, 3, . . . }.
Glossary
http://www.amathsdictionaryforkids.com/
Capture 5
Materials:
100 chart, deck of Change Cards*, 12 mark-
ers of one color, game piece for each player, paper.
Players:
Two players or two teams
How to Play:
The object is to collect 5 game markers.
1. Place 12 markers on the 100 chart, so each marker is
on a different number. Deal 5 “change cards” to each
player or team and place the remaining cards face
down. Players put their game pieces anywhere on the
100 chart.
2. On a turn, move your game piece using any combi-
nation of your change cards to land on a square with a
marker. You can use any number of cards from 1 to 5.
3. If you land exactly on a square with a marker, capture
it by taking it off the board. You can only capture one
maker during a turn, and it must be the last square you
land on.
4. Record your moves in an equation. If you begin on
45, and use the cards +2, +10, +3, you record: 45 + 2 +
10 + 3 = 60.
5. Place the “change cards” you used face down in a
discard pile. Take cards from the top of the deck to re-
place them. If the deck of “change cards” is use up,
shuffle the discard pile and turn it face down again.
6.The first player or team to capture 5 markers wins.
*You can make your own Change Cards by cutting
small pieces of paper and labeling them:
Four of each: +1, -1, +2, -2, +10, -10, +20, -20; Two
each: +3, -3, +30, -30 (forty cards total)
You can also create your own 100 chart or get one from
your
1 2 3 4 5 6 7 8 9 10
teacher.
11 12 13 14 15 16 17 18 19 20
21 22 23 24 25 26 27 28 29 30
31 32 33 34 35 36 37 38 39 40
41 42 43 44 45 46 47 48 49 50
51 52 53 54 55 56 57 58 59 60
61 62 63 64 65 66 67 68 69 70
71 72 73 74 75 76 77 78 79 80
81 82 83 84 85 86 87 88 89 90
91 92 93 94 95 96 97 98 99
100
