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Presented to the 2012 Annual Conference American Mathematical Association of Two-
Year Colleges Jacksonville, Florida November 8, 2012
By Joyce Lindstrom, Ed.D.
Shipping –competes with
Rotterdam as busiest port in the
world
Education – develop the best
education system in the world so
the people could become the
natural resource
Preserve ethnic identities
While I am happy that
Singapore has been able to
develop a first-world
economy so quickly, what
does that have to do with
teaching math in the US?
Fourth grade Eighth grade
Country
Average
score Country
Average
score
International average 495 International average 466
Singapore 594 Singapore 605
Hong Kong SAR1,2 575 Korea, Republic of 589
Japan 565 Hong Kong SAR1,2 586
Chinese Taipei 564 Chinese Taipei 585
Belgium-Flemish 551 Japan 570
Netherlands2 540 Belgium-Flemish 537
Latvia 536 Netherlands1 536
Lithuania3 534 Estonia 531
Russian Federation 532 Hungary 529
England2 531 Malaysia 508
Hungary 529 Latvia 508
United States2 518 Russian Federation 508
Cyprus 510 Slovak Republic 508
Moldova, Republic of 504 Australia 505
Italy 503 United States 504
Australia2 499 Lithuania3 502
New Zealand 493 Sweden 499
Scotland2 490 Scotland1 498
Slovenia 479 Israel 496
Armenia 456 New Zealand 494
Norway 451 Slovenia 493
1) Curriculum Design based on
research
Jerome Bruner from Poland
Richard Skemp from England
Zoltan Dienes from Denmark
To instruct someone... is not a matter of getting him to commit results to mind. Rather, it is to teach him to participate in the process that makes possible the establishment of knowledge. We teach a subject not to produce little living libraries on that subject, but rather to get a student to think mathematically for himself... Knowing is a process not a product.
(1966: 72)
To understand something is to relate
it to what is already known…
Without the prerequisite knowledge…
the result is rote learning, or no
learning at all.
SAIL: Structured Activities in Intelligent Learning:
SAIL Design Strengths
Conceptual understanding from Kindergarten
Algebra in the 8th grade
Geometry with proofs in the 9th grade
2) Professional Development of
Teachers
100 hours every year
Events provided by or funded by
the Ministry of Education
Lesson Studies
Shared teacher-created resources
Missouri law requires individuals with Initial Professional Certificates (IPC) to complete 30-contact hours of professional development during the first four years of teaching.
Individuals with Career Continuous Professional Certificates (CCPC) must complete 15-contact hours each year.
Missouri Department of Elementary and Secondary Web Site 2011
Michael and Joris baked 64 chocolate chip
cookies. The ratio of the number of cookies
Joris baked to the number of cookies Michael
baked was 5:3. How many fewer cookies did
Michael bake than Joris?
Mathematics PSLE Revision Guide, 2nd Edition, Michelle Choo
Copyright 2009 p. 181
Michael and Joris baked 64 chocolate chip cookies. The ratio of the number of cookies Joris baked to the number of cookies Michael baked was 5:3. How many fewer cookies did Michael bake than Joris?
Michael’s cookies
Joris’ cookies
? 8 units = 64
1 unit = 8
2 units = 16; Michael had 16 cookies more than Joris
Of the people in attendance at a recent
ball game, one-third had grandstand
tickets, one-fourth had bleacher tickets,
and the remaining 11,250 people in
attendance had other kinds of tickets.
What was the total number of people in
attendance at the game?
Richard Bisk Copyright 2007 Used by permission
Of the people in attendance at a recent ball game, one-third had
grandstand tickets, one-fourth had bleacher tickets, and the
remaining 11,250 people in attendance had other kinds of tickets.
What was the total number of people in attendance at the game?
To solve by bar modeling:
1/3 1/4
1/3 1/4
Grandstand
tickets
11,250
tickets
Bleacher
Tickets
Bleacher
tickets
Grandstand
tickets
11,250
tickets
? 5 units = 11,250
1 unit = 11,250/5 = 2,250
12 units = 27,000
27,000 people attended the game
In 1983, prior to implementing this
curriculum, Singapore ranked 17 out of 26
countries tested in eighth grade
Mathematics.
Just twelve years later, in 1995, Singapore
ranked number one out of 41 countries
tested at that level and remained number
one in both 1999 and 2003.
Dr. Richard Bisk Copyright 2007 Used by Permission
In 1960 of the 30,615 students who sat for
the Primary School Leaving Exam, 45%
passed.
In 2010, of the 45,049 students who sat for
the Primary School Leaving Exam, 97.3%
assessed as suitable to proceed to secondary
school.
Because kids are visual, model drawing helps
students “see” relationships
Model drawing makes more complex word
problems possible
Number bonds are essential in early grades
Most important training is on-the-job
New/experienced teachers observe each
other’s classrooms
Ministry Of Education supports education
with professional development and classroom
resources
752.3
748.3
750.2
759.3
761.2
771
735
740
745
750
755
760
765
770
775
2006 2007 2008 2009 2010 2011
M
A
P
I
N
D
E
X
YEAR
3RD GRADE MATHEMATICS 6 YEAR TREND SINGAPORE MATH ANALYSIS
State
Wentzville
Timeline of implementation: 2008 = 160 students participated in an after school program 2009 = majority of 1st, 2nd and 3rd teachers were using Singapore Math in the classroom.
We saw higher student
achievement out of the
classrooms that used Singapore
Math. All grade levels improved…
We are very pleased with the
results and we hope to continue
to see the scores improve. Gregg Klinginsmith, Math Curriculum Coordinator, personal email, 8/15/2010
6÷1/2 = ? And why?
Compute mentally: 12 x 97
John spent 2/7 of his money on a storybook.
The storybook cost $16. How much money
did he have at first?
Let’s try 6÷2. How many 2’s are there in 6?
There are three 2’s in 6, so 6÷2 = 3
What about 6÷3? How many 3’s are there in 6?
There are two 3’s in 6, so 6÷3 = 2
2 2 2
3 3
How many (1/2)’s are there in 6?
There are twelve (1/2)’s in 6, so 6÷(1/2) = 12
1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2 1/2
John spent 2/7 of his money on a storybook. The storybook cost $16. How much money did he have at first?
?
John’s money
$16
2 units = $16
1 unit = $8
7 units = $56
John had $56 at first.
Keane bought some marbles and gave half of them to Leon. Leon bought some stamps and gave half of them to Keane.
Keane used 5 stamps and Leon gave away 11 marbles. The ratio of the number of stamps to the number of marbles Keane had left then became 1 : 7 and the ratio of the number of stamps to the number of marbles Leon had left became 1 : 5.
How many stamps did Leon buy?
Kentucky Town and Merrily Town are 234 km apart.
Dawn left Kentucky Town for Merrily Town at 8.42
a.m. travelling at an average speed of 85 km/h. At
the same time, Jennifer left Merrily Town for
Kentucky Town. They met each other at 10.30 a.m.
(a) What was Jennifer’s average speed when she
met Dawn?
(b) If Jennifer were to increase her speed by 26
km/h before meeting Dawn, how much lesser time
would she take before meeting her?
1. Ali has $8 more than Sid. Trina has
$6 less than Ali. The three of them
have $76 in all. Find the amount of
money each of them has. Yeap Ban Har, Bar Modeling, A Problem-Solving Tool, p. 37
2. Chris started saving some money
on Monday. Each day she saved $2
more than the day before. By
Friday of the same week Chris had
saved $35. Find the amount Chris
saved on Wednesday. Yeap Ban Har, Bar Modeling, A Problem-Solving Tool, p. 40
3. There were 3 times as many
girls as boys on a bus. There were
twice as many children as adults.
There were 36 persons altogether
on the bus. How many girls were
on the bus? Yeap Ban Har, Bar Modeling, A Problem-Solving Tool, p. 56
4. Kumar took 5 days to read a book. He read 1/9
of the book on Saturday, 1/4 of the remainder on
Sunday, and the remaining 48 pages during the last
three days. How many pages were there in the
book? Cynthia Seto, Teaching Fraction, Ratio and Percentage Effectively,
p. 49
5. The ratio of the number of boys to the number of
girls in a school hall was 5:7. After ½ of the boys
and 63 girls left the hall, there was an equal
number of boys and girls remaining in the hall. How
many girls were there in the hall at first? Cynthia Seto, Teaching Fraction, Ratio and Percentage Effectively, p.
80
6. There were 126 children at a
concert. The number of boys was ¾
as many as the number of girls. When
an equal number of boys and girls left
the concert, the number of boys and
girls remaining at the concert was 5:7.
How many boys left the concert? Cynthia Seto, Teaching Fraction, Ratio and Percentage Effectively,
p. 79
9. The number of balls in Box A is ½
of the number of balls in Box B. 10%
of the balls in Box A and 10% of the
balls in Box B were moved to Box C.
As a result, the number of balls in
Box C increased by 20%. There are 72
balls in Box C now. How many balls
were there in Box B at first? [RGPS 2010 SA1 Q16]
10. Dolly had 80 more stickers than
Jenny. Dolly gave 25% of her
stickers to Jenny.
Jenny in return gave 60% of her
stickers to Dolly. In the end, Dolly
had 100 stickers more than Jenny.
How many stickers did Dolly have
at first?
[NHPS 2010 SA1 Q18]
11. The tickets for a show were priced at
$10 and $5. The number of ten-dollar
tickets available is 1½ times the number
of five-dollar tickets. 5 out of 6 ten-
dollar tickets and all the five-dollar
tickets were sold. The amount of money
collected from the sale on the tickets
was $5600. How much more would have
been collected if all the tickets were
sold? [Ai Tong 2010 CA1 Q10]
12. How many gallons of 50%
antifreeze must be mixed with 80
gallons of 20% antifreeze to obtain a
mixture that is 40% antifreeze? Lial, Hornsby, McGinnis Beginning and Intermediate Algebra, 4th
Edition, p. 158
13. Airplanes usually fly faster from west to
east than from east to west because the
prevailing winds go from west to east. The
air distance between Chicago and London is
about 4000 miles, while the air distance
between New York and London is about 3500
miles. If a jet can fly eastbound from
Chicago to London in the same time it can fly
westbound from London to New York in a 35-
mph wind, what is the speed of the plane in
still air? Encyclopaedia Britannica, quoted in Lial, Hornsby, McGinnis Beginning
and Intermediate Algebra, 4th Edition, p. 451
14. Ms. Teng, a high school mathematics
teacher, gave a test on perimeter, area,
and volume to her geometry class. Working
alone, it would take her 4 hours to grade
the tests. Her student teacher, Jonah
Schmidt, would take 6 hours to grade the
same tests. How long would it take them
to grade these tests if they work together? Lial, Hornsby, McGinnis Beginning and Intermediate Algebra, 4th
Edition, p. 452
Keane bought some marbles and gave half of them to Leon. Leon bought
some stamps and gave half of them to Keane.
Keane used 5 stamps and Leon gave away 11 marbles. The ratio of the
number of stamps to the number of marbles Keane had left then became 1 : 7
and the ratio of the number of stamps to the number of marbles Leon had
left became 1 : 5.
How many stamps did Leon buy?
Leon’s stamps
Keane’s stamps
Leon’s marbles 11
Keane’s marbles
5
Keane bought some marbles and gave half of them to Leon. Leon bought
some stamps and gave half of them to Keane.
Keane used 5 stamps and Leon gave away 11 marbles. The ratio of the
number of stamps to the number of marbles Keane had left then became 1 : 7
and the ratio of the number of stamps to the number of marbles Leon had
left became 1 : 5.
How many stamps did Leon buy?
Leon’s stamps 1 unit
?
Keane’s stamps 1 unit-5
Leon’s marbles 11
Keane’s marbles
5
Keane bought some marbles and gave half of them to Leon. Leon bought
some stamps and gave half of them to Keane.
Keane used 5 stamps and Leon gave away 11 marbles. The ratio of the
number of stamps to the number of marbles Keane had left then became 1 : 7
and the ratio of the number of stamps to the number of marbles Leon had
left became 1 : 5.
How many stamps did Leon buy?
Leon’s stamps 1 unit 1 unit
Keane’s stamps 1 unit
-5 5
Leon’s marbles 1 unit 1 unit 1 unit 1 unit 1 unit 11
Keane’s marbles 1 unit 1 unit 1 unit 1 unit 1 unit 1 unit 1 unit
- 5 -5 -5 -5 -5 -5 -5
From the last two lines:
5 units + 11 = 1unit -5 + 1 unit –5 + 1 unit – 5 + 1 unit – 5 + 1 unit – 5 + 1 unit -5 + 1 unit – 5
5 units + 11 = 7 units – 35
11 = 2 units – 35
46 = 2 units, which is the number of stamps Leon bought
Kentucky Town and Merrily Town are 234 km apart. Dawn left Kentucky Town for Merrily Town at 8.42 a.m. travelling at an average speed of 85 km/h. At the same time, Jennifer left Merrily Town for Kentucky Town. They met each other at 10.30 a.m.
(a) What was Jennifer’s average speed when she met Dawn?
(b) If Jennifer were to increase her speed by 26 km/h before meeting Dawn, how much lesser time would she take before meeting her?
Kentucky 234 km Merrily
Town Town
85 km/h ------- ------? km/h
8:42 am 10:30 am 8:42 am
Dawn ----------------------------------------------------------------------Jennifer
8:42 to 9:00 is 18 minutes; 9:00 – 10:30 is 90 minutes, so the two cars travel for 108 minutes before they meet.
108 minutes = 108/60 hours = 9/5 hours
Dawn traveled 85 km/hr x 9/5 hr = 153 km
Jennifer traveled 234 km – 153 km = 81 km
To travel 81 km in 9/5 hr, Jennifer traveled 81/(9/5) = 45 km/hr
Kentucky Town and Merrily Town are 234 km apart. Dawn left Kentucky Town for Merrily Town at 8.42 a.m. travelling at an average speed of 85 km/h. At the same time, Jennifer left Merrily Town for Kentucky Town. They met each other at 10.30 a.m.
(a) What was Jennifer’s average speed when she met Dawn?
(b) If Jennifer were to increase her speed by 26 km/h before meeting Dawn, how much lesser time would she take before meeting her?
Kentucky 234 km Merrily
Town Town
85 km/h ------- ------ 71 km/h
8:42 am ? 8:42 am
Dawn -------------------------------------------------------------------------Jennifer
Jennifer is now traveling 45 + 26 = 71 km/hr, so
Dawn and Jennifer are heading toward each other at 71+85 = 156 km/hr
They will meet in 234 km ÷ 156 km/hr = 3/2 hr = 90 minutes
The time this change would save is 108 minutes – 90 minutes = 18 minutes
t
10t
10t - 1
Divisible by
9?
Divisible
by 11?
10t + 1
Divisible
by 11?
0
1
2
3
4
5
6
Let n = at x 10t +… + a2 x 102 + a1 x 101+ a0 x 100
Complete this table:
t
10t
10t - 1
Divisible
by 9?
Divisible
by 11?
10t + 1
Divisible
by 11?
0 1 0 Y
1 10 9 Y
2 100 99 Y
3 1,000 9,99 Y
4 10,000 9,999 Y
5 100,000 99,999 Y
6 1,000,000 999,999 Y
Let n = at x 10t +… + a2 x 102 + a1 x 101+ a0 x 100
Complete this table:
For example: 53,812 can be written as:
(5 x 9999) + (3 x 999) + (8 x 99) + (1x 9) +
Divisible by 9
+ (5 x 1) + (3 x 1) + (8 x 1) + (1 x 1) + (2 x 1)
Divisible by 9?
Conclusion: A number is divisible by 9 if and only if the sum of the digits is a multiple of 9.
t
10t
10t - 1
Divisible
by 9?
Divisible
by 11?
10t + 1
Divisible
by 11?
0 1 0 Y N 1
1 10 9 Y N 11
2 100 99 Y Y 101
3 1,000 9,99 Y N 1,001
4 10,000 9,999 Y Y 10,001
5 100,000 99,999 Y N 100,001
6 1,000,000 999,999 Y Y 1,000,001
Let n = at x 10t +… + a2 x 102 + a1 x 101+ a0 x 100
Complete this table:
t
10t
10t - 1
Divisible
by 9?
Divisible
by 11?
10t + 1
Divisible
by 11?
0 1 0 Y N 1 N
1 10 9 Y N 11 Y
2 100 99 Y Y 101 N
3 1,000 9,99 Y N 1,001 Y
4 10,000 9,999 Y Y 10,001 N
5 100,000 99,999 Y N 100,001 Y
6 1,000,000 999,999 Y Y 1,000,001 N
Let n = at x 10t +… + a2 x 102 + a1 x 101+ a0 x 100
Complete this table:
t
10t
10t - 1
Divisible
by 9?
Divisible
by 11?
10t + 1
Divisible
by 11?
0 1 0 Y N 1 N
1 10 9 Y N 11 Y
2 100 99 Y Y 101 N
3 1,000 9,99 Y N 1,001 Y
4 10,000 9,999 Y Y 10,001 N
5 100,000 99,999 Y N 100,001 Y
6 1,000,000 999,999 Y Y 1,000,001 N
Let n = at x 10t +… + a2 x 102 + a1 x 101+ a0 x 100
Complete this table:
Also, 53,812 can be written as:
5(9999) + 3(1001) + 8(99) + 1(11) +
Divisible by 11
+ 5(1) – 3(1) + 8(1) – 1(1) + 2(1)
Divisible by 11?
Conclusion: A number is divisible by 11 if and only if the number formed by (sum of odd-position digits) – (sum of even-position digits) is a multiple of 11.