By Laura Pan
My 3rd grade teacher introduced the metric system to my class and predicted that in our lifetimes the U.S. would convert from the British system of weights and measures to the metric system. That was many years ago and while products on the shelves of U.S. stores today display both measurements, I’m still buying my gasoline in gallons instead of liters.
Honestly, how many Americans pay attention to the metric equivalents on packaging? The 11-oz can of mandarin oranges means that I have a little over a cup—and I can picture the measuring cup right away—but if you told me that I have a little over 300 grams no image comes to mind at all. It’s not natural. I know that 2.54 centimeters is equivalent to 1.00 inch, but absolutely nothing comes to mind when it comes to converting grams to ounces.
And that’s the point. It’s not about conversion, but basic number sense. Until we can re-establish our number sense, we simply won’t use the metric system like the rest (94%) of the world. But maybe there’s still a chance in my lifetime.
Math Challenge: With Thanksgiving fast approaching, how easily could you prepare your meal if you used metric measurements only?
Check out this metric-based Turkey Roasting Guide.
If you can’t complete the challenge, try working on your metric number sense by using (and possibly replacing) metric system equivalents in your recipes with the help of the following guide.
| If Using... | Replace With |
| 1 dry oz. | 28 grams |
| 8 dry oz. (1/2 pound) | 230 grams |
| 16 dry oz. (1 pound) | 450 grams |
| 1 teaspoon | 5 mL |
| 1 tablespoon | 15 mL |
| 1/4 cup (2 oz.) | 60 mL |
| 1/2 cup (4 oz.) | 120 mL |
| 2/3 cup (5.3 oz.) | 160 mL |
| 3/4 cup (6 oz.) | 180 mL |
| 1 cup (8 oz.) | 240 mL |
