The MidSchool Math Conference

The next MidSchool Math conference is already in the planning stages

The next MidSchool Math conference is already in the planning stages

My presentation on Math and the Metric System: Using What’s Easy at the MidSchool Math conference went very well. The session had 50 people registered and while not everyone showed up, most folks did. Since the attendees were mostly math teachers I felt I had an opportunity to get them thinking about the metric system in new ways that they could take back their classrooms and hopefully their lives. The group was receptive and had lots of questions for me. They were also able to interact and ask each other questions about their metric classroom experiences.

Hands-on opportunities

I had scheduled some hands-on exercises using length and mass to help them get used to applying metric units. While length didn’t present much of a problem, only a couple of people used scales in the kitchen. This gave them a chance to play with some of the equipment I brought. (Let’s face it, pretty much every ruler and tape measure today has both U.S. customary and metric units on them but most people are so familiar with measuring cups that it doesn’t occur to them to use a scale in the kitchen though it’s far easier.)

I also brought some metric-only rulers supplied by the National Institute of Standards and Technology (centimeters on one side, millimeters on the other) and they cleaned me out of those—which I consider a good sign.

Avoid conversions!!!

A couple of folks on the U.S. Metric Association (USMA) listserve who communicated with me prior to my talk wanted to make sure that I didn’t encourage conversions during my presentation. Not only was that explicit in my presentation—twice no less—but I also pointed out that I’d gotten that feedback from USMA to try to drive the point home. I think it worked.

After all, the metric system was introduced at a time of widespread illiteracy and even unschooled french farmers and tradesmen learned it easily enough. It should be a cinch for today’s high-tech Americans.

One attendee told me she thought it was the best presentation she’d seen so far (I was in the afternoon on the second day) but I have to say that the keynote speaker on the first day, Dan Meyer, was extremely good. He stressed the need to engage kids studying math in the classroom in three acts and bring them along for a story where they really want to figure out what happens. Let’s face it, everyone gets more interested if there’s a good story involved. I think the audience heard him.

Testing my story structure

For my part, I got a chance to try out part of my story structure for the documentary on an audience, hear questions and find out what parts of the narration were of the most interest by their level of attention. There’s just nothing better than trying out your material on a real audience. I’m very pleased with the results but I will continue to refine and expand.

Since I did attend a couple of sessions other than my own, I also had a chance to engage with additional teachers and all seemed very interested in what I’m trying to do. It was only one of the other presenters who gave me pause when he suggested that the next generation would take care of metric conversion in the United States. (Only other time I’ve heard that before [good idea but not now] was in John Quincy Adams’ report to Congress back in 1821—haunts us every time we get serious about metric adoption by the way…) I quickly realized that there was no point in arguing the issue with him but would have loved to point out that in the 30 years since the U.S. Metric Board was disbanded no “next  generation” has come along so far and perhaps he’s part of the “next generation” that should do something. Ah well, I tried to be as persuasive as possible under the circumstances.

As should always be the case, the teacher and learner roles got reversed during my session and I walked away with some additional things to think about and research.

For instance:

  • I’ve been told the military uniformly uses the metric system but others have told me that’s not true. True status will take some digging.
  • When converting from miles to kilometers, what happens to the mile markers since they’re currently used to help drivers know how many miles to their next exit?
  • What’s the best way to convert existing recipes into metric?

The cost of conversion

Of course, the biggest unanswerable question I get asked is how much would it cost to convert to the metric system in this country. I don’t think anyone has a good grasp on that since it’s been so long since the question was seriously considered.

Aside from the cost of conversion errors, and time savings in schools and elsewhere on an individual basis, imagine how much time it takes to design things for multiple countries with dual labeling—including the use of more ink to print both sets.

Converting to the metric system will have a mostly one-time cost while failure to convert to the metric system continues to cost us, and cost us and cost us…


Metric Conversion and “Rational” Sizing

I’m learning lots of new things as a result of this project and a concept I became aware of early on was “rational sizing.” I’m writing about this subject now because there’s been a lot of traffic on this idea on the U.S. Metric Association’s listserve under the name “oddball measurement.”

What it basically means is that when moving from U.S. customary units to metric ones, things might not end up with what some people call “rational” (or rounded) numbers. I was also told by a reliable source (thought I have to admit that I have not yet confirmed this) that rational sizing was one of the points of resistance by the food industry back during our last metric push in the mid 1970s.

I’ll try to explain:

If you have a traditional U.S. eight-ounce container and you want to move to the metric system, you have two options 1) retain the same packaging and “re-label” (though metric units are on most American packaging) the container as 236.588 milliliters (not sure how precise labels need to be), or 2) you resize the package to something that seems more “rational” like up to 250 mL or down to something like 230 mL. Apparently, in some people’s minds numbers that end in zeros or represent commonly used numerical breakdowns such as 25, 75 are more “rational.” I don’t personally have that bias but different minds work in different ways. (I supposed a third option would be to keep the packaging size the same and round down the milliliters it contains to a rounded amount but that doesn’t seem to be the direction most companies take.)

GlueFor example: within my reach (I’ve confessed to my laziness before) is a bottle of Elmer’s Craft Glue. Its label states that it holds “4 FL OZ (118 mL).”

My understanding (and I’ll confess to being overly dramatic here) is that 30 years ago the food industry in this country had two objections to going metric and one related to rational sizing. “Oh my God,” said the food industry, “if we go metric we’re going to have to move to rational sizing, which means we’ll have to change all of our packaging, and that will be expensive, and then nothing will fit correctly on the shelves in the stores, and we’ll have to change the size of the shelves as well. That’s an impossible thing to ask us to do.”

I consider this argument poppycock and not the popcorn kind.

When the time comes (though I don’t expect to have any actual say in the matter), just take the customary units off and let the metric units stand on their own until a redesign dictates new packaging and then make a minor adjustment in the volume if having a “rational number” is all that important (and I’m not convinced it is). Heck, I could see manufacturers use their traditional “sleight of hand” and make the packaging slightly smaller and keep the prices right where they are. This has historically been done many, many times and Consumers Reports magazine highlights these sorts of tricks on a regular basis.

Sutter_labelActually, after a quick look around, I now have in front of me a bottle of Sutter Home Champagne Vinegar and its label reads “12.7 FL. OZ. (375ml).” In this case, it’s the milliliters that are “rational” and yet I bought it even before I started my metric quest. I’m sure at the time, having a less rounded number for ounces didn’t phase me in the slightest.

So, if you hear the “rational sizing” argument thrown around in future in a move to the metric system, at least you’ll have some background on what it’s all about.

As far as I’m concerned, rational sizing is not a rational argument.


Note: The phrase “rational number” in the above context does not represent its true arithmetic meaning. For more information on that use see Be prepared that most definitions I found required an understanding of the words “integer” and “quotient.”

Metric Resources (A World to Share)

In the half year that I’ve been working on this project, it has been my pleasure to come in contact with a number of metric like-minded folks who have been moving in this direction far longer than I. I’d like to take this opportunity to share their sites with you in case you find them of interest. (I sure hope so or else why are you reading this thing?)

National Institute for Standards and Technology—U.S. Department of Commerce
There is tons of information on the main website at, If you want to drill down to the metric system resources, they’re under the Physical Measurement Laboratory ( and then you get down to the resources for the metric system:

U.S. Metric Association
There is a phenomenal amount of information on this organization’s pages and it’s been around since 1916. (I love people who don’t give up the good fight.) It was the extremely sad litany of information on this page ( that led me to embark on my current quest. Feel free to look around and join the organization. I’m sure they’d love for you to sign on as a member and it’s only $30 a year (see page for multi-year discounts) to help along its fine work.

The Reddit Metric Pages
Reddit, which refers to itself as “The frontpage of the Internet,” has its own metric posting pages. The metric section already has more than 5,000 members and it’s free to join in: There are also now subpages devoted to metric cooking: Come on in and look around. You might decide to stay for awhile.

The Metric Maven
The Maven has spent considerable thought on metric issues and shares his insights on his blog, which he adds to on a regular basis. Yes, we cross promote because we’re both heading in the same direction. Just makes sense to me. Go to to read more.

Metric Pioneer
Another advocate, this site describes itself as “ is dedicated to United States President Andrew Johnson and to Metric Pioneer Antoine Lavoisier (1743–1794 CE) Father of Modern Chemistry, who helps construct the metric system during the French Revolution while working alongside Benjamin Franklin in France.” Metric products are for sale here. As far as I know, he’s currently got this market cornered. Check it out:

M Power
One of the first people to reach out to me, the lady behind this site states: “Our goal is to empower K-12 students to succeed in Science, Technology, Engineering, Mathematics, and Military (STEMM) by preparing them to think in STEMM’s occupational language.” Find out more at Another nonprofit organization, help out if you can.

National Council of Teachers of Mathematics
While this might seem like a niche organization, these are the folks are the keepers of National Metric Week (the week in which November 10 falls [as in 10/10]). Its mission: “The National Council of Teachers of Mathematics is the public voice of mathematics education, supporting teachers to ensure equitable mathematics learning of the highest quality for all students through vision, leadership, professional development, and research.” More at

U.K. Metric Association
This organization has been supportive of my efforts from early on. While the U.K. is mostly metric, it’s not all the way there and we’re holding them back. Let’s stop that. For more information, go to

National Measurement Institute
I have it on good authority that Australia has embraced the metric system and Imperial units are difficult (if not impossible) to find—which is a sign of real success. This is a country we may want to emulate when our time comes. For more information, go to

I know less about these folks, but they’re out there so let’s cheer them on:

Go Metric USA
Its pages state: “GO metricUSATM is an organization dedicating to promoting the adoption of the metric system in the United States of America and to help industries cut costs.”

Go Metric America
Don’t know much about this either, but it follows me on Twitter and frequently retweets me. Its Facebook page states that its cause is to “Educate, promote and encourage daily usage of the Metric System. Make SI the only measurement standard of science, math, industry, trade, and education in the USA.” Here is its link on Twitter and Facebook

Metricate America (Metric8America)
Don’t see a website for this one, but the Twitter page is

If I’ve missed you, I apologize. Let me know. Relevant ones can always go into another blog on the subject.