Conceptual math help, please.

[Tabrett]

This is really embarrassing, but in Singapore Earlybird 2A US edition p.18 and 19 it teaches that:

 

*** *****

3 is ___less than 5.....I know the answer is 2 but,

 

Why teach it that way? You would never set up a problem that looks like this:

3-___=5

 

In the next two pages it confuses me again. It states that:

 

5 is ___more than 3....again I know the answer is 2 but,

 

a problem would never be set up as

 

5+___=3 unless you were using negative numbers.

 

Why are they teaching it backward? Why not teach that;

3 and 2 more is 5

5 less 2 is 3

 

Is it not confusing to teach-how many more less than a larger number?

 

Why not just teach the <,> signs and leave the terminology of 'more' to mean addition and 'less' to mean subtraction?

 

This type of terminology confuses me, I can't possibly imagine a 5yo understanding what he is being asked to do. He didn't have any problem repeating how the 'picture' shows how to do the problems, but was this truly understanding and why would a 5yo need to understand this type of terminology anyway?

[Snowfall]

My DD is not advanced in math, but this sort of problem is common in MEP Yr. 1, and DD totally gets it. The reason for it is because it helps kids to understand what all that terminology means. What does it mean for 3 to be 2 less than 5? It means the same as 3+2 or 5-2. It's important for a kid to really, really understand that 3+2 and 5-2 and and 2+3 and 5-3 are all really part of the same thing, which is....I don't know...FIVEness. lol

 

Oh, but I'm not sure it's important for a FIVE yo, to understand that. You're not doing 5yo math, though. You're doing 7yo math if you're doing 2A, aren't you? It is important for them to understand that at some point. :)

Edited September 9, 2010 by Snowfall

[Tabrett]

You're doing 7yo math if you're doing 2A, aren't you? It is important for them to understand that at some point. :)

 

I'm doing Earlybird 2A not Primary 2A. Earlybird is kindergarten. :D This terminology was also used in RS. I COULD not figure out how to explain how a number that is less is more less than a larger number.

 

What is the purpose of this? Saying a number is how many more less just doesn't make sense to me.

[Snickerdoodle]

"Is" means equals

 

so

 

3 is __ less than 5

 

is a subtraction problem

 

3 = some amount less than 5

 

or

3= 5-2

[5LittleMonkeys]

It's teaching the relationship between numbers and it's teaching terminology to prepare them for critical\word problems.

 

You won't always see 2+3=?, sometimes you will find a problem such as: If David has 3 apples and Jill has 2 more then how many apples does Jill have? OR David has 1 apple, Tony has 1 less than Jill. Jill has 5 more than David. How many does Tony have?

 

I've not used Singapore but MEP does this a lot as well as a lot of algebraic preparation such as balancing equations. It is all to thoroughly prepare them for math concepts they will face from this age on up.

[Whereneverever]

It's showing different ways to work the numbers bonds. Later Singapore also talks about how 5=3+2 or 3+2=5- that the = or is isn't tied to one side or the other.

[siloam]

It's teaching the relationship between numbers and it's teaching terminology to prepare them for critical\word problems.

 

You won't always see 2+3=?, sometimes you will find a problem such as: If David has 3 apples and Jill has 2 more then how many apples does Jill have? OR David has 1 apple, Tony has 1 less than Jill. Jill has 5 more than David. How many does Tony have?

 

I've not used Singapore but MEP does this a lot as well as a lot of algebraic preparation such as balancing equations. It is all to thoroughly prepare them for math concepts they will face from this age on up.

I agree with Amie, it is also helpful when you are doing number bonds.

 

That said these are the reasons why I don't use Singapore Earlybird anymore. While I think it is important to teach it, I don't think K is the developmentally appropriate time.

 

You can just skip it, or re-write it for now. It will be covered again later.

 

Heather

[crazyforlatin]

Those problems can be difficult for a K'er, but since DD knows her math facts, I give her problems like these to challenge her. We don't use Earlybird, but CWP1 has them.

[Tabrett]

"Is" means equals

 

so

 

3 is __ less than 5

 

is a subtraction problem

 

3 = some amount less than 5

 

or

3= 5-2

 

Thank you. I understand now. I didn't realize that 'is' meant =. I was associating the less than with the number 3 and not the number 5.

 

But still, why would you want to teach 3 is 2 less than 5 BEFORE you teach 5 less 2 is 3 or 3 and 2 more is 5.

 

3+2=5 and 5-2=3 both go in numerical order. You could count, use a number line or abacus to demonstrate both problems. When you say 3 is ___less than 5 you have to start with the 5 subtract the 3 to fill in the middle blank. It goes out of numerical order. Even when you showed 3=5-2 you had to flip the order of the 2 and 5 from their original positions.

It just seems like a backwards and confusing way to introduce a subject.

Edited September 9, 2010 by Tabrett

[Snickerdoodle]

I think this article explains it well:

In the course of this kind of teaching I came to the conclusion that teaching to under-

stand and intelligently use the natural language, in the present case English, is one

of the most urgent functions of mathematical education.

How I teach Word Problems

 

Can you see if this link works? I'm on a Mac now and still learning it's tricks.

[siloam]

But still, why would you want to teach 3 is 2 less than 5 BEFORE you teach 5 less 2 is 3 or 3 and 2 more is 5.

 

 

 

I can't answer why, my gut is that they are building a fluency with numbers, so the child doesn't always see numbers as equations. But that said I would just restate the problem, "What would have need to add to 3 to make 5?" After the child said 2 then I would restate the original problem, "That means that 3 is 2 less than 5."

 

Heather

 

[crazyforlatin]

I think this article explains it well:

 

How I teach Word Problems

 

Can you see if this link works? I'm on a Mac now and still learning it's tricks.

 

It works! Thank you for this article because I have been thinking hard on word problems and the importance of teaching and how to teach them. Telling DD to answer 13-7 is easy for her, but translating to that from English gets me this response :confused:. So when we see "fewer than" I tell her to draw a box around it and translate that into, for example, - 7.

[Tabrett]

I can't answer why, my gut is that they are building a fluency with numbers, so the child doesn't always see numbers as equations. But that said I would just restate the problem, "What would have need to add to 3 to make 5?" After the child said 2 then I would restate the original problem, "That means that 3 is 2 less than 5."

 

Heather

 

 

I wouldn't have a problem teaching it like you stated or saying if I have 5 and want to make it into 3 how many do I need to remove? So, 5 less 2 is 3.

 

Maybe it is just how my mind works. Geometry was easy for me because it had pictures. The only way I could solve Algebra problems was to draw pictures and insert the numbers into the drawing (I had a fantastic college professor that taught me how to do this).

[Guest]

It's teaching the relationship between numbers and it's teaching terminology to prepare them for critical\word problems.

 

You won't always see 2+3=?, sometimes you will find a problem such as: If David has 3 apples and Jill has 2 more then how many apples does Jill have? OR David has 1 apple, Tony has 1 less than Jill. Jill has 5 more than David. How many does Tony have?

 

I've not used Singapore but MEP does this a lot as well as a lot of algebraic preparation such as balancing equations. It is all to thoroughly prepare them for math concepts they will face from this age on up.

 

That's how I saw it also. They are trying to teach the concepts of (the idea behind) addition and subtraction before teaching the mechanics. This is an area that I always did well in and my son seems to be that way also and this is one of the reasons Singapore Math has worked well for us. I find it is things like this that make me decide if a program is what I am looking for or not. When doing PK we were using a program that had you ease a student into concepts by teaching them something that did not always apply, which meant that I would have to re-teach in the future correcting this idea by explaining that this only applies at certain times. Well, I know my son, if I did that he would stick to what he knows and defend it to death :lol:. I used the curriculum but since I know he has no problem grasping mathematical concepts I just taught it correctly from the start using my own way. It was one of the things that made me realize that this was not a curriculum I wanted to use in the long run even though it has worked well for others. I would use things like this to help me determine if the program is what I am looking for or not ;).