Word Problems and Bar Models from Literature

I’ve enjoyed Denise Gaskin’s Let’s Play Math blog since at least 2007!  I shared her site when the problems for Mr. Popper’s Penguins were first published.

She has a new book of word problems tied to literature: Word Problems from Literature: An Introduction to Bar Model Diagram

I immediately bought a copy for my Kindle (a steal at only  $3.99).

Here’s a sample from the chapter entitled Moving Toward Algebra: Challenge Problems:

Denise provides step-by-step solutions with bar models. Here’s just a teaser of the solution to Han Solo’s problem:

This looks to be a great resource for some motivating and just darn fun problems.

Enjoy!

 

 

Singapore Tops TIMSS 2015!

The 2015 Trends in Math and Science Study (TIMSS) results were recently published. Students in fourth and eighth grades from more than 40 countries worldwide participated in the most recent test. This test marks a 20-year span of comparative mathematics and science achievement data collected and once again East Asian countries topped the charts.

What does the TIMSS test?

The TIMSS tests students’ math and science knowledge. For the sake of this post, we are going to focus on mathematics. Both content domains (Number, Geometry, and Data) and cognitive domains (Knowing, Applying and Reasoning) are tested every four years.  Student achievement is then compared to other participating countries.  Singapore’s students once again ranked number one in the world, marking the fifth time Singapore has scored highest on the TIMSS  since the country first participated in 1995.  Students in the United States trail students in Singapore by 79 points for fourth grade and 103 points for eighth grade.

TIMSS Results for Select Countries – Fourth Grade Mathematics

1995 2003 2007 2011 2015
         
Singapore 625 (1) 594 (1) 599 (2) 606 (1) 618 (1)
Hong Kong-SAR 587 (4) 575 (2) 607 (1) 602 (3) 615 (2)
Republic of Korea 611 (2) 605 (2) 608 (3)
Chinese Taipei 564 (4) 576 (3) 591 (4) 597 (4)
Japan 597 (3) 565 (3) 568 (4) 585 (5) 593 (5)
Russian Federation 532 (9) 544 (6) 542 (9) 564 (7)
England 513 (16) 531 (10) 541 (7) 542 (9) 546 (10)
United States 545 (11) 518 (12) 529 (11) 541 (11) 539 (14)
Average* 529 545 500 500 500

* International Average in 1995 and 2003, Scale Average since 2007

How challenging are the questions?

The questions on the TIMSS can be broken down into four levels, or benchmarks; Advanced, High, Intermediate and Low. The examples below are from fourth-grade problems.

A low-level question tests basic mathematical knowledge:

Percentage of students able to answer a low-level question: 99% Singapore, 98% U.S.

 

An intermediate level question tests the ability to apply basic mathematical knowledge in simple situations:

Percentage of students able to answer an intermediate level question: 93% Singapore, 79% U.S.

 

A high-level question tests the ability to apply mathematical knowledge and understanding to solve problems:

Percentage of students able to answer a high-level question: 80% Singapore, 47% U.S.

 

An advanced level question tests the ability to apply knowledge and understanding in a variety of relatively complex situation and to explain mathematical reasoning:

Percentage of students able to answer an advanced level question: 50% Singapore, 14% U.S.

To sum it up, students in the U.S. are really good at solving basic computation questions but struggle with applying their knowledge to solve problems in high and advanced level questions.

For more information about the TIMSS and a complete report, visit http://timssandpirls.bc.edu/timss2015/.

How does Singapore do it?

In a nutshell, a Singapore Math curriculum focuses on deep conceptual understanding and problem-solving with an emphasis on the “why” over the “how” of math.  Concepts are introduced, practiced to mastery and immediately applied to solve both familiar and novel problems. Students are given ample time to grapple with problems to find multiple solutions which develops flexibility with numbers and logical thinking.

In contrast, traditional curricula in the U.S. has tended to focus on memorization and procedures. “Ours is not to reason why; just invert and multiply.”  Math has been taught as a series of steps to follow to tackle what appear to be unrelated concepts. Many concepts are taught per grade level with little time to practice and master before moving on to the next concept; often referred to as a spiraling curriculum. This limits deep mathematical understanding.

What can we do?

There’s still hope. There are a few curricula in the U.S. that follow the Singapore math approach to deepening mathematical understanding and problem-solving.  You can read more about Primary Mathematics and Math in Focus here.

If you are not in a position to change your curriculum, you can integrate some of the best strategies from Singapore into your current curriculum.  Take time to teach basic concepts to mastery, focus on developing number sense with mental math activities and help students to visualize word problems with bar modeling.

Each year more and more schools, school districts and home-schooling parents are making the switch, but just buying new textbooks is not enough. Professional development and teacher training is an often overlooked piece of the puzzle. (That’s where Math Champions comes in. For information on how we can help you use Singapore Mathematics,  please complete the form or send us an email.)

[contact-form to=’cassy@mathchampions.com’ subject=’TIMSS Post Help’][contact-field label=’Name’ type=’name’ required=’1’/][contact-field label=’Email’ type=’email’ required=’1’/][/contact-form]

 

Source: TIMSS 2015 International Results in Mathematics. Copyright © 2016 TIMSS & PIRLS International Study Center, Lynch School of Education, Boston College, and
International Association for the Evaluation of Educational Achievement. All rights reserved.

 

 

Number Talks in the Classroom (Part 2)

elevateFrom our previous post on Number Talks, we explained how to establish a safe and respectful classroom environment and shared examples of appropriate topics of Number Talks in Kindergarten through 5th grade. Read Part 1.

Number Talks in Action

Environment plays a key role. Students should gather at a designated meeting area in the classroom away from writing materials or have writing materials tucked away if working at desks.  I’ve allowed students to sit on top of desks just for this purpose.

The following outlines the flow of a Number Talk.

 

Teacher: Students:
Teacher writes 27 + 18 on the board. “When you have found one way to solve it hold up your thumb.  If you can think of a second way to solve it, add a finger.” Holding up their thumbs if they have found a strategy to solve the problem.  Adding in fingers for each additional strategy they come up with.
Teacher: Students:
“Let’s share answers.” Teachers records all answers, right or wrong. “48, 47, 45”
Teacher: Students:
“Would anyone like to argue for or against one of the answers?”

Teacher records strategies on the board as students share, and labels them with numbers and/or student names.

“I agree with 45 because I know I need to add 2 to 18 to make it 20, and I can get the 2 from the 27 which leaves me with 25 to add to 20, which makes 45.”

“I disagree with 48 because you would need to add 30 to 18 to make 48 and you only have 27.”

“I disagree with 47 because you would need to add 20 to 27 to get 47 and we only have 18.”

“I also agree with 45 because I know that 20 and 10 makes 30 and 7 and 8 makes 15 and 30 and 15 is 45.”

“I also agree with 45 because I know I need to add 3 to 27 to make it 30.  I can get 3 from 18 which leaves me with 15 and 30 and 15 is 45.”

Teacher: Students:
“It looks like we have 3 strategies that work to get us the answer of 45 and are able to disprove the other two answers.  Can we all agree that 45 is the answers?”

“If you had a similar problem to solve, show with your fingers, would you choose strategy 1, 2 or 3?”

Teacher could use this time to discuss efficiency of strategies.

Students hold up 1, 2 or 3 fingers to choose their strategy of choice.
Teacher: Students:
Teacher writes 38 + 23 on the board.

“I want everyone to use strategy 3 (or other strategy of teacher’s or student’s choice) to solve this problem.

“When I count down from 3, say the answer.  3-2-1…”

Teacher clarifies any remaining confusion, if necessary.

Students holding up thumbs and fingers when they have solved the problem and say answer when prompted by the teacher.

Looking for a way to deepen number sense, build confidence and celebrate different ways of thinking?  Then, give Number Talks a try!  Please comment and share your experience.

Number Talks in the Singapore Math Classroom (Part 1)

elevateMental math plays a huge role in the Singapore Math curriculum.  By developing mental math strategies in your students, you are equipping them with strong number sense, a critical skill and goal for our students to reach by the end of middle school.

You can practice mental math in your classrooms with a Number Talk; a term coined by Sherry Parrish in her popular book, Number Talks: Helping Children Build Mental Math and Computation Strategies.

Establishing Rules and Roles for a Number Talk

For Number Talks to be successful, you have to establish some rules for respectful listening and productive criticism.  All students need to feel safe to participate without feeling ridiculed.

Enlisting student help when generating rules allows students to take ownership of them and creates a classroom where the rules are more likely to be followed.

To generate rules for Number Talks you might ask:

What does it look and sound like when someone is being a good listener?

It’s equally important to teach students how to respond to each other in a respectful manner.  In a recent post on Edutopia, Oracy in the Classroom, types of talk were artfully organized into 6 discussion roles.
stw-school21-typesoftalk

During a Number Talk, students become the Builders, Challengers and Clarifiers, while the teacher plays the roles of the Instigator, Prober, and Summariser as he or she guides the discussion as the facilitator of the Number Talk.

What should we talk about?

In Kindergarten, Number Talks can focus on subitizing and connecting the pictorial to the abstract.

Thoughtful problems are used in grades 1 through 5, designed specifically to practice mental math strategies that have been introduced in class.

In Kindergarten, show an image like this and ask, “How many dots do you see?”

screenshot-61

In first grade, show an image like this.

screenshot-62

Or a problem like this to practice addition strategies.

18 + 5 =

In second grade, start with a problem like this to practice addition strategies.

57 + 14 =

Or this, to practice adding a number close to 100.

97 + 33

Or this, to practice subtraction strategies.

43 – 28 =

In third grade, start with this to practice mental math with multiplication.

14 x 3 =

Or this to practice mental division.

42 ÷ 3 =

In fourth grade, start with problems like these to build on strategies learned in the previous grades.

499 + 137 =

138 – 56 =

In fifth grade, start with problems like these to continue to build on strategies learned in the previous grades.

1388 + 2983 =

29 x 7 =

135 ÷ 5 =

Give some of these a try and check back soon for the next installment of Number Talks in the Singapore Math Classroom.

Look for Part 2 next Monday!

About that “Singapore Math” Problem that has Gone Viral

If you spend much time on the internet, you are probably aware that a math problem from Singapore is in the news. It challenges readers to determine Cheryl’s birthday based on an impossibly small set of clues.

In a report, the New York Times compared this problem to that of the “color-changing dress that blew out the neural circuits of the internet.” The story’s headline: “A Math Problem from Singapore Goes Viral.” Wow. The world’s response to the “Cheryl’s Birthday question” has inundated my “Singapore Math” Twitter feed. The problem:SASMO_Cheryl_s_Birthday_jpg

Are you smarter than a ten 14-year old?

Some initial reports suggested that this “Singapore Math” problem was appropriate for primary grade students. The Guardian initially asked: “Are you smarter than a Singaporean ten-year old?” Fortunately, the true source emerged rather quickly. This problem was part of a Math Olympiad challenge that organizers thought could be answered by only 40% of the most gifted high school students. This prompted the Guardian to instead ask: “Are you smarter than a Singaporean 14-year old?”

As we now know, this is not really a problem asked in any classroom using a Singapore Math curriculum. In fact, it isn’t really a math problem; instead, it is a logic problem. And a really challenging one at that.

Many of those who commented said something to the effect that, “it made my brain hurt.” Others chose to rant about Cheryl; this was the approach of the New Yorker in its Daily Cartoon for April 16. [Need help with the problem? See “How to Figure Out Cheryl’s Birthday” by New York Times science writer Kenneth Chang.]

In the midst of all the noise, there were a few responses that offered some clarity.

In a video clip, the Globe and Mail said that the problem, “tapped a nerve…our math phobia.” John Mighton, founder of Jump Math says that this is a universal problem.

I KNOW that math anxiety is a reality, and one that I address in almost every encounter with teachers and parents.

Why Singapore’s students are so good at math

But most insightful of all may be the assessment of Libby Nelson of Vox.com. Early in her piece, she says:

But the problem isn’t nonsense: it’s actually a test of logical reasoning skills. And questions like these help explain how Singapore’s students have come to rank as some of the best problem-solvers in the world — by being taught math differently, and well.

A 2005 study from the American Institutes for Research praised Singapore’s method of teaching math, saying it was much better than the American method. On reason was that word problems and real-world examples were used not just to show students that math is important outside the classroom, but to illustrate how math works.

This brings to mind my favorite quote about Singapore’s approach to teaching math from Dr. Yeap Ban Har:

We’re not teaching math, we’re teaching thinking through the medium of math.

Nelson discusses how Singapore’s students acquire problem-solving skills and become so good at math before asking whether Singapore’s methods can work in the U.S.

After working with more than 100 schools using Singapore’s Math curriculum, I know the answer to Nelson’s last question is an unqualified “YES.”


Ready for Another Problem?

The Singapore and Asian Schools Math Olympiads (SASMO), creators of the Cheryl’s Birthday problem, have posted a new challenge. It also features Cheryl, this time with new pal Tom. Can you figure this one out?

SASMO Challenge

The problem and solution are on SASMO’s Facebook page.