kitchen table math, the sequel: Challenging Word Problems to be discontinued

Sunday, April 12, 2009

Challenging Word Problems to be discontinued

A bit off the latest controversial topics, but I thought readers of this board would want to know that the Singapore Math series: Primary Mathematics Challenging Word Problem from EPB Pan Pacific is being discontinued. According to the publisher, these books are:
"Highly recommended for capable students as a source of interesting review and challenging word problems"
If you've ever used the books, you know what a loss this will be to future users. While the books may be relics compared to the current Singapore Syllabus, one can't help wonder if the changes in the "Teach Less, Learn More" syllabus in Singapore haven't contributed to the country's ever so slight drop on the most recent TIMSS.

SingaporeMath.com may have most books in the series available through summer, although it sounds like Primary 3 is in short supply.

For your problem-solving enjoyment, here's a sample from the end of the Primary 6 book - Challenging level:
Cindy had four times as many postcards as Annie. After Cindy gave 20% of her postcards to Jane and Annie gave 10% of her postcards to Jane, the number of Jane's postcards increased by 75%. If Jane had 252 postcards in the end, how many postcards did Cindy have at first?
Have fun!

11 comments:

GoogleMaster said...

The Cindy/Annie/Jane problem is exactly the type of problem I loved solving when I was 12 or so. My parents bought me entire books of these things that I read/played with (can't say worked on; it wasn't work!) while we sat in waiting rooms or in the car on long trips.
.
I wish they wouldn't dumb down the textbooks just because Brittni Average doesn't understand or like them. Save something for the motivated/interested students!
.
I went to engineering school because I enjoyed solving equations and word problems, and I knew there would be lots of them in engineering. :-)
.
Ummm, looks like Cassy threw out a challenge there at the end. Okay, I could do this easily with algebra, but let's see what happens without...
.
Jane ended up with 252 postcards, which was 75% more than she started with, so she started with 252*4/7 = 144 postcards. Jane's increase was 252-144 = 108 postcards, which is 20% of Cindy's plus 10% of Annie's. But Cindy started with four times Annie's starting amount, so 20% of Cindy's initial number is the same as 80% of Annie's initial number. So Jane's increase of 108 postcards was equal to 80%+10%=90% of Annie's initial number, so Annie started with 120 postcards. Cindy started with four times as many, or 480 postcards.
.
Start:
Cindy: 480 postcards
Annie: 120 postcards
Jane: 144 postcards
.
Transferred to Jane:
Cindy: 96 postcards
Annie: 12 postcards
total: 108 postcards
.
End:
Cindy: 384 postcards
Annie: 108 postcards
Jane: 252 postcards

concernedCTparent said...

Cassy- thank you.

What a shame. My kids really love CWP. Looks like I'll be stocking up on a number of grade levels. I appreciate the heads-up.

concernedCTparent said...

I just ordered the grade levels I was missing (and I guess the kids won't be writing in the workbooks anymore so we can hand them down).

BTW- I noticed the book Singapore Model Method of Teaching Math highlighted on the homepage at singaporemath.com. I imagine it's a book on teaching with bar modeling (I'm too tired to look right now). What do you think of it?

LynnG said...

I, too, love those Challenging Word Problems. I also like Intensive Practice from the SM series. These are so challenging, you have to sprinkle them in. Average kids (i.e., kids that can do math but are not wired to enjoy it) can only take so much Challenging Word Problems or Intensive Practice before they rebel. I'll be ordering mine from grade 3 through 6 now, so I don't run out when I need them.

TerriW said...

I just ordered up a copy of each one. We're only halfway through the first one, but silly me, I thought we'd be able to use these as workbooks, so we wrote in it. I guess we'll be using these as texts from now on...

Thank God they're cheap.

I don't like what this portends for the future, though.

Saxon is becoming less Saxon, and now Singapore is looking like it's going to be less Singapore.

Great.

Dawn said...

I have 3 and 5 but I'll have to stock up on the rest though.

The other book from Singaporemath.com that we love is Brain Maths 1 (anyone else use that?). Catherine and I were actually having fun with that one tonight and I was planning to order Brain Maths 2...Might as well make it a bigger order then planned.

rocky said...

Why does it seem like "cheating" to use algebra to solve Singapore Primary 6 problems? I figure if a kid can translate the problem into these three equations, it's worth at least 40%...

c = 4a

20c 10a 75j
--- + --- = ---
100 100 100

175j
---- = 252
100

Then if he can solve for c and write "Cindy had 480 postcards", it's worth the rest.

My theory is that the reason only ten people could understand Archimedes was because geometric algebra is a lot harder than symbolic algebra.

The Singapore bar models are a great introduction, just like the little balancing shapes on scales or seesaws, but the goal is to start using equations.

SteveH said...

"...but the goal is to start using equations."

We've talked about this on other threads and most all would agree with this statement.

I would give students more than 40%, especially, if they showed that they could "turn the crank" from past problems.

On some problems, bar models cause the solution to jump right out into your face. This doesn't always happen, especially if the numbers or proportions are not nice. With equations, it doesn't matter what the numbers are.

From a more philosophical angle, how valuable is it to tackle problems that have two equation and two unknown algebraic solutions before students have had any algebra - all in the hopes of developing understanding or problem solving skills? If you do a bar model and it helps you "see" the solution, how do you feel when you can't "see" it on another problem? Do you feel that you have to work harder at bar models? Should mastering bar models be a goal? I don't think so. I worry more that educational faddists will adopt it as their own.

I'm a big fan of introducing variables and simple equations in earlier grades. It's easier to translate simple word problems into equations if you have just one equation, even if you could solve it in your head.

rocky said...

From a more philosophical angle, how valuable is it to tackle problems that have two equation and two unknown algebraic solutions before students have had any algebra - all in the hopes of developing understanding or problem solving skills?

Exactly right. Do those "cow and chicken" problems with the heads and legs give children confidence or even teach them anything? Or do they reinforce the notion that you need a special knack to solve math problems and those without the knack have to guess and check and fill out tables of busywork.

Translating words into equations is something anyone can learn and it is the key to power in algebra! It is the mind of man dancing with the beauty of God's creation!

Oh. I guess I shouldn't get so carried away.

Anonymous said...

"I'm a big fan of introducing variables and simple equations in earlier grades. It's easier to translate simple word problems into equations if you have just one equation, even if you could solve it in your head."

I can add some anecdotal evidence to this. My 3rd grader is working through Singapore Math (with me ... we homeschool). Except that we don't use bar models. Which sounds like it should be heresy when using SM.

But ... his handwriting/penmanship/drawing skills are pretty bad (we are working on them...) and my judgment was that *drawing* would make the math more difficult for him that just going straight to equations.

So far, the "straight to equations" approach has worked fine. It wasn't *too* hard to move from "5 + ___ = 8" to "5 + X = 8" and then ramp from there.

So ... I can offer one story where this seems to be working just fine. I don't think it even occurred to him that he was supposed to be afraid of the 'X'.

-Mark Roulo

CassyT said...

I worry more that educational faddists will adopt it as their own.

Too late.
enVision Math has adopted and adapted the bar model method:
"“A new approach to solving
word problems . . . is to
use bar diagrams as visual
representations . . .”

After watching their promotional video, my Buzzword Bingo card was a cover-all winner.