Metric System - a Failure!

Discussion in 'Elementary Education' started by foxgallagher, Feb 6, 2008.

1. foxgallagherRookie

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Feb 6, 2008

I am attempting to teach the metric system to my fourth grade class. I tried with a number line and moving the decimal however many hops today, but the students gave me the deer-in-the-headlights look. They are ALL confused...even the ones at the top of the class! I will be trying to teach this again tomorrow (if we don't have a snow day - right now it's like a blizzard outside and we could end up with 12 inches). Does anyone have any ideas for getting metrics to make sense?

3. bonnebFanatic

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Feb 6, 2008

I'm sorry fox. I am a failure with metrics personally. Bumping you up so someone else might be able to answer. I know you will hit on it. Good for you for seeing the approach wasn't working! That to me is the sign of a true teacher - willing to see and admit something is not working, then mulling it over to find a better way!

4. MrsCMultitudinous

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Feb 6, 2008

Metric is all we learn and teach, so not sure how much help I'll be. What concepts do you need to teach? I would start with the basic linear units--millimetre, centimetre, decimetre, metre, etc. and discuss what objects we would measure with these. Measure objects in the classroom using various units--how many mm, cm, m? (Just FYI, although decimetre, decametre and hectametre make the conversions easier, they aren't used anywhere other than in school--at least I never have). We use a "stair-step" model when teaching conversions between units--each step up is 10 of the previous unit. (does that make sense?) The same prefixes are used for measures of capacity (litres) and mass (grams).

Interestingly, we use metric measurements for almost everything, but everyone knows their height in feet and inches and their weight in pounds.

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Feb 6, 2008

Try money. That's a metric measurement.

6. foxgallagherRookie

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Feb 6, 2008

MrsC - I've already had them measuring with meters and centimeters. They've seen millimeters on the ruler and know about how small they are (we demonstrated how to estimate these in class). I have heard of the stair step method, but I don't know that it will work. I'm not sure my students understand the concept of decimals much.

I may try to teach this without the line and hops first (between meter, centimeter, and millimeter). Once I get this established, I would show them on the line so they could see how the line worked. Then I could move on to kilometers. Of course, I'd be alternating between meters, grams, and liters at some point to make sure they understood these are all base units.

7. foxgallagherRookie

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Feb 6, 2008

Thanks for the vote of confidence! I can tell you now that as soon as I got the look of confusion I was thinking to myself...oh boy. I'm in for it now....

8. kcjo13Phenom

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Feb 6, 2008

I teach my kids the same with customary as metric. I teach my kids:

SMALLER to LARGER = DIVIDE
LARGER to SMALLER = MULTIPLY
(then we think of pneumonics (sp?) to remember these by-this year they came up with Slow Lazy Donkey, Lazy Slow Mule)

Then we learn the conversion factors. Kilo=1000, centi=100, etc. So when you are converting, you use the conversion factor, and decide whether to divide or multiply.

142 km (larger) = ___________ m (smaller)
Multiply 142 x 1000 = 142,000 m

This is really hard to explain by typing! I hope this makes sense. My kids have always caught on really well, and I make a big deal about how I am "converting" them to metric 'cause it's easier. I tell them they are learning things that their parents refused to 20 years ago!

If I haven't explained this well enough, let me know, I'll try again.

9. TeacherGroupieModerator

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Feb 6, 2008

Have you got a meter stick? Walk the kids through measuring your desk or part of a whiteboard or something that's between one and three meters in length: first they measure the desk (say) in millimeters and record the result on the whiteboard, then they measure it in centimeters, then they measure it in meters. With luck, someone will notice that what's being measured is the same AND that the digits stay the same - all that seems to have happened is that the decimal point has migrated. Tell 'em this is what makes the metric system handy: for example, instead of having to memorize that there are 16 of one kind of ounce in a pound and 32 of another kind of ounce in a quart, we just have to remember that deci- is like a dime and centi- is like a penny compared to a whole dollar.

10. RainStormPhenom

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Feb 6, 2008

I think one of the reasons teaching metric is so hard is that, as people from the US, we so rarely use metric. If you ask me how long the desk is, I'm going to estimate in inches. That is just how my brain was trained to work.

When we are asked to teach something we aren't totally comfortable with, it becomes even harder to do.

The other thing that I think makes it harder than it should be is that here, in the US, we teach our children centimeters and meters in elementary school. We often mention that milimeters are those little tiny lines.

We don't teach it as 10 milimeters makes a centimeter. 10 centimeters makes a decimeter. 10 decimeters makes a meter. Etc. So the children never seen "why" metric is easy to use. They don't understand moving the decimal point, because we never teach decimeters. It isn't part of the curriculum.

11. LoomistroutDevotee

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Feb 6, 2008

That's a great description :lol::lol:

They may be experiencing cognitive overload trying to remember too many skills at once. You may have done this. Consider introducing meter or milli' but never at the same time. In other words don't include moving decimal until class has lots and lots of practice with *one* concept at a time. So they measure stuff in milli' only until they drop -- say minimum 16 practices.

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Feb 7, 2008

I think this is your problem - until they get decimals (which is pretty much all we use - money, measurement, temperature, stockmarket, etc) it's going to be really hard for them to understand why they are moving the decimal point and which is bigger.

When my kids get confused with, say 2.78 x 1000, I tell them to just concentrate on the units column - so 2 units x 1000 become 2000, the other digits fall into line behind with how ever many zeroes on the end to hold them in their correct place value column. That's the abbreviated version.

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Feb 7, 2008

And the practice time is the thing. Every time I have my kids measure in metric over and over I start to wonder why I'm doing it since they probably will never choose to use metric in the real world (US).

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Feb 7, 2008

And why do we only have soda in liters and no other liquids sold that way here?

15. TeacherGroupieModerator

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Feb 7, 2008

No other liquids sold that way?? Au contraire (or, if you prefer, eau contraire): bottled water is metric at least as often as it's not. And wine and hard liquor have been metric since the late '70s. Olive oil tends to be metric, especially when imported, as does balsamic vinegar.

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Feb 7, 2008

As a member of the fake world I wonder why would anyone use any other system?

Power to the Powers of Ten!:2up:

17. foxgallagherRookie

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Feb 7, 2008

Everyone's given me a lot of great input. Thanks! I love the idea of multiplying and dividing, but a lot of my kids don't understand the concept of division yet. That fact alone makes it much harder.

Personally, I had wanted to take 3 days or so to try and teach it (knowing it would probably take longer), but my host teacher was pushing me to do it in two lessons. The way the lesson day fell, it ended up being my long science day, so the lesson were back to back. That could have been part of the problem too.

The first 40 minutes I actually did have the students measure the height of the white board in centimeters and meters (1.5 meters). They noticed the fact that 100 centimeters lined up with 1 meter without me even telling them to look! However, when it came time to start trying to convert, they all lost that fact.

Luckily, they called school off last night (and I'm afraid to look outside and see how much ended up getting dumped on us). I don't get to teach science again until Tuesday, so I have all weekend to try and figure this out.

18. SchoolRocksCompanion

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Feb 7, 2008

I thought I have heard of using base ten blocks to teach metric??? I could be wrong, but I think each block can represent a power of ten?? Then the kids can draw the decimal that each block represents. I also have a sheet from my undergrad called "MEtric Me". The kids measure all different parts of their bodies in different units. For example, for the neck they measure the perimeter, weight- kg, area of a footprint, temperature-celsius, height-meters... If you are interested pm me and I can list all of the measurements for you to use.

19. 3SonsEnthusiast

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Feb 7, 2008

*groans*

Did you feel compelled to inflict that pun on us, TG?

You mean, 30cm?

20. TeacherGroupieModerator

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Feb 7, 2008

(meekly)

I can't help it. It's part of my oral tradition.

Last edited: Feb 7, 2008
21. ChpriceNew Member

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Feb 7, 2008

Hello. This particular concept is that one my students struggle with more than anything (conversions within the metric system). I would appreciate ANY tips/ideas from any willing soul to help me with getting this concept across to my students. I will try anything!!!

22. ChpriceNew Member

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Feb 7, 2008

Mrs LC.......I think I'm going to try this. This makes complete sense!

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Feb 7, 2008

Well, their real world, in the U.S., is where they have to function. I'd rather use the metric system, too. It is much easier. Whoever said that the kids have to know how to multiply decimals before making sense of the conversions is right.

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Feb 7, 2008

25. blue-eyed momCompanion

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I've used this way for a long time and it's very successful for me!

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