Right STart B Lesson 23 ?

[happyhappyjoyjoy]

So far we've loved all of RS B. I'm a little thrown in Lesson 23.

 

When looking at the number 20:

Why does she have you point to the 2 and say 2, but then point to the 0 and say 10? This makes no sense to me.

 

Why does she say this in the NOTE section:

Thinking of numbers in columns hampers their full understanding of place value.

 

I learned in columns and I picked up place value just fine. I just can't rap my head around point to 20 and saying 2 while pointing to the 2 and ten while point to the 0. I also don't get pointing to 200 and saying 2 while point to the 2, hun while pointing to the first zero, and dred while pointing to the final zero. (this last example is in lesson 25.)

 

All help is greatly appreciated.

Thanks:)

[Joyofsixreboot]

Because 20 is 2 tens. It's about the 'asian' way to count. It will pay off. Two ten 3 is 23, etc. The traditional english counting is taught later.

[truebluexf]

Basically, what she's saying is you have 2-tens even because of the zero. If it was 21, you'd say say "two ten one." This is just a way to really solidify place value.

[happyhappyjoyjoy]

I get all of that. I don't understand why you don't point at the 2 in 20 and say 2-ten. Why do you say ten when pointing at the 0? If looking at 200, why would you say "hun" when pointing at the tens column and "dred" when pointing at the ones column? Why does she discourage teaching by columns???????

[truebluexf]

It really all makes sense as you go on and see the lightbulbs go on. Honestly, my son understands place value way better than I ever did. I did the work, but certainly didn't understand what I was doing. I would say just let this one point go and carry on. ;) If you want her own explanation, I'd try the RS forums, people from RS will answer your questions there.

[happyhappyjoyjoy]

i will if i don't get more replies here, but i'm hoping to hear from others.

[FairProspects]

I get all of that. I don't understand why you don't point at the 2 in 20 and say 2-ten. Why do you say ten when pointing at the 0? If looking at 200, why would you say "hun" when pointing at the tens column and "dred" when pointing at the ones column? Why does she discourage teaching by columns???????

 

I think it is because children more readily understand that it is the 0 after the 2 that changes its value rather than the 2 itself (which is inherent in Asian numbering schemes but not in English). This way 2 always means 2, and it is the 0 (or other symbols) after it that changes the designation.

 

She doesn't do it with 200, because the RS grouping system doesn't work that way. 200 is not 2-hundred (well later it is, but not at first), but 20-ten. The Asian system is very different than teaching by columns, but personally, I think more effective. Columns can sometimes be thrown off by handwriting or placing, where grouping & an inherent understanding of what place value is, cannot be. Columns are not necessary if you already have grouped in your head (the mental math part of RS) based on an understanding of place value.

 

I hope that makes sense!

[Kuovonne]

The purpose of pointing to the zero in 20 is to emphasize the number of digits in the number.

 

A number in the "tens" place, has one digit after it, so you point to the zero to emphasize that connection.

 

A number in the "hundreds" place, has two digits after it, so you point to the two zeros as you say each syllable in "hundred".

 

A number in the "thousands" place, has three digits after it, so you point to the three zeros as you force a third syllable into the word "thousand."

 

If I recall correctly, you only point in this way with the place value cards, where there are zeros to point to, and not numbers with different digits in each place value. Then you will layer the place value cards to make multi-digit numbers. This will eventually lead to understanding that writing digits next to each other makes multi-digit numbers.

 

More food for thought: my preschool daughter started recognizing the numbers 1-9 a while ago. Recently, she started asking me questions like, "what is 2 and 4?". I thought she was asking me what is 2 + 4. Then I realized that she was looking at the number 24. She was seeing the 2 and 4 as separate numbers, not a single number with digits in different place values. When it's her turn to do RightStart, she'll no longer make these mistakes.

[siloam]

i will if i don't get more replies here, but i'm hoping to hear from others.

 

Feel free to slightly modify it. You can easily point to the 2 and say 2, then ask what place value is it sitting in. Hopefully they answer 10's and you then tell them that means this is 2-tens. And if the 2-ten name drives you nuts then simply say that means this is two tens, or twenty.

 

No need to get bogged down on the details, make it work for you.

 

Heather

[SnegurochkaL]

Because 20 is 2 tens. It's about the 'asian' way to count. Two ten 3 is 23, etc.

 

Hi, I just will give you an example of Japanese counting:

25 is ni-ju-go (two ten five )

100 is hyaku (one hundred)

125 is hyaku ni-ju-go (one hundred two ten five)

220 is nihyaku ni-ju (two hundred two ten)

 

1000 is sen (one thousand), it is getting confusing after that because

10,000 is ichiman (one ten thousand).

 

As for us, instead of saying 25 as "two ten five" my daughter was saying "two tens and five", which had more sense for her.

[Haiku]

Why do you say ten when pointing at the 0?

 

Because by noticing that the number is made up of two digits, you are noticing that the number is a tens number. It's more for rhythm (think clapping syllables) than anything else. You aren't saying that the 0 is a ten.

 

If looking at 200, why would you say "hun" when pointing at the tens column and "dred" when pointing at the ones column?

 

Same thing: rhythm. Three syllables ("two-hun-dred,"), three digits.

 

Tara

[Satori]

I think I understand the poster's confusion. Saying "ten" on the "ones" place is indeed a little confusing! I see what everyone's saying, but I think Tara explained it the best. Saying it this way is an easy way to incorporate rhythm so you can remember the different place values.

[happyhappyjoyjoy]

Yes, thank you Tara. That was super helpful!!!!