# I seriously need some help with math

Discussion in 'Elementary Education' started by 5throx, Jul 29, 2010.

1. ### 5throxRookie

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Jul 29, 2010

I'm a first year fifth grade teacher, and I realized yesterday when I started trying to teach place value that I have no idea how to teach math. All the math I taught in practicums and student teaching was either scripted or gave very specific activities. Now I'm on my own with my own kids the first unit in our program (which is just a big book of math problems) is place value, powers of ten, and decimals. I'm at a loss as to what to do for this.
Later stuff in the year like factoring, probability, stuff like that I'm more okay with teaching, but this stuff? I have no clue! Any ideas and input would be great!

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Jul 29, 2010

Well, I won't comment on how much this bothers me (beyond what I'm saying right now), because it is what it is...

So... what specifically are you teaching? Place value is a big concept. What are the standards you are covering?

4. ### PeachynessVirtuoso

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Jul 29, 2010

They should already know ones all the way to billions, if not further. I think the toughest ones are the tenths, hundredths, etc. I emphasize that there are no "oneths" and we say it a few times because it sounds so silly. Have the kids come up with crazy numbers with long decimals and make it into a game to figure out what places values those numbers are.

5. ### 5throxRookie

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Jul 29, 2010

What I'm struggling with is reading and writing numbers in standard and expanded form... fortunately my kids get the standard form thing, it's expanded form that they don't get and I don't know what to do.

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7. ### 5throxRookie

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Jul 29, 2010

Thanks Peachyness! By the by, what did you search? I swear, I spent two hours browsing the internet a few nights ago!

8. ### PeachynessVirtuoso

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Jul 29, 2010

I just typed place value expanded form.

Also, feel free to check out my math resource website. It's still a work in progress (still adding more websites/documents).

9. ### novalyneRookie

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Jul 29, 2010

The issue here that they need to understand is that a digit has two functions - the digit number itself, and the value of the digit according to its place value. Example: In the number 3,257 - 2 is the digit, but it's worth 200 b/c it's in the hundreds place.

If they are really struggling, you could have them act it out and form "human numbers". Start with just a few kids - maybe 4 (to the thousands place). Each kid gets a place value - hang it on a sign around their necks (thousands place, hundreds place, tens place, ones place). Then give each student a random digit. Put them in line in the correct place-value order (thousands, hundreds, tens, ones). Have each child show their number to the class and explain what they're worth ("I have an 8 and I'm the thousands place so I'm worth 8,000", etc.). The rest of the class can write down each number value on a whiteboard or piece of paper. Then they add them together and see that they come up with the original number.

You can switch out students and make the number longer each time. After a few rounds (so each student gets a turn being a place value), they should get it and be able to start working it out with practice problems on paper.

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Jul 29, 2010

Essentially for expanded form, you're breaking the number down into its parts.

38,281 = 30,000 + 8,000 + 200 + 80 + 1

Adding all those parts together will give you the whole. I would demonstrate using base ten blocks...

So 2,582 = 2 cubes (thousands), 5 flats (hundreds), 8 rods (tens) and two units (ones).

If they're able to demonstrate the number using base ten blocks, they should be able to start on expanded form by thinking what each group actually represents. So 2 cubes is equivalent to 2000, 5 flats is equivalent to 500... etc. etc.

11. ### Love to TeachCohort

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Jul 30, 2010

As Novalyne was pointing out, it is so important that the kids make the distinction between "place" and "value". It takes some kids a while to understand this.

Example: 2,365,987
The "place" that the 2 occupies is millions.
The "value" (what it is worth) is 2,000,000.

In practicing the different forms, we use the acronym SEW:
S=standard form
E=expanded form
W=written form

With the expanded form, have them start with the highest place value, take that digit and then add zeros for each digit to the right. Then, take the next highest place and repeat, etc.

Back to the example:
2 million is your highest place value digit, so take the 2 and add six zeros to represent each of the digits to the right of the 2. Then take the 3 and add zeros for each of the numbers to the right. They can use their finger or a small piece of paper to cover up each digit they have already used, if they need to.

2,000,000+300,000+60,000+5,000+900+80+7

For the written form, tell them to read the number to themselves and then write it exactly as they "say" it. Break it down one 'period' at a time, taking care to insert the commas after each written period.

Example:
1st 'period'
two million.....say it and write it exactly as you say it, add a comma

2nd 'period'
three hundred sixty-five thousand...say it and write it exactly as you say it, add a comma

3rd 'period'
nine hundred eighty-seven

two million,three hundred sixty-five thousand, nine hundred eighty-seven

Make sure that they spell the words correctly, put in the commas to separate the periods, and that they include the hyphens properly. Some may want to say "nine hundred and eighty-seven"...be sure that they don't do that. It is improper and will cause HUGE problems when they start writing out decimal numbers.

Practice, practice, practice with them. Take random numbers and tell them to "SEW" them. Make charts where they fill numbers into the proper places. Have them roll dice to make the largest number possible by placing the numbers rolled into a chart. Turning notebook paper sideways makes a quick chart...works well when multiplying and dividing, too.

Actually, by 5th grade, most students should have place value to the millions down well. Our 5th grade text adds whole numbers to the billions and decimals to the ten thousandths. Most just need a good review, but a few still do struggle. Good luck.