This is one in a continuing series of activities that takes mathematics and applies it to social issue, including Food Waste and Mathematics: From Farm to Table to Dump, Mathematics, Demographics & Slavery: The 1790 Census in Ratio, Percents & Graphs, MathBusters: Percentage Practice to Analyze 2016 Election Results, and Statistics, Histograms and Lies Presidential Candidates Tell. In this case, we are looking at how far food must travel in order to make it from where it is produced to the place where it is actually consumed.
In this era of a global food supply (which is not so new, by the way: remember, Columbus sailed the ocean blue in 1492 because he was looking for a quicker way to transport spices from India to Europe), the issue of local food production has been of greater concern, especially when it comes to concerns about nutrition (foods that sit for long periods of time lose their vitamins quickly), the local economy (as local farms disappear due to competition from foreign imports) and maintaining a diverse food supply (having access to lots of different types of foods, instead of just a few), not to mention concerns about food safety (some imported foods have been found to cause outbreaks of various diseases.) All in all, there is a lot to be said about preserving the availability of local foods on your table, and this activity examines these issues using mathematics.
This series of activities begins by looking at the places where common foods originate, including “staples” like sugar, coffee, chocolate and pepper. Allow students to work on their own to hypothesize where foods come from and then check their guesses with the actual country of origin. These are not necessarily the largest producers of foods, but where a student living in the United States is most likely to get their food from. For example, the US imports coffee from many countries in South America and Africa, but the average person is probably going to be drinking coffee from Brazil (although the range of coffee producers at your local Starbucks is pretty dizzying, including Timor, Guatemala and Rwanda.)
The second part of the lesson is to compare foods that are sold at a local farmer’s market (hopefully there is one near you; field trip!) and then recording the location of the farms from which they came. I provided several different kinds of foods to investigate, so that they have some flexibility at looking at what’s being sold at your farmers’ market, including dairy, fruit, vegetables, poultry and grains. Of course, since I live in bougie-bougie Brooklyn, our farmers’ market sells croissants, exotic mushrooms and, believe it or not, there is one stand dedicated to lavender.... go figure.
Finally, there is a “share out” where students weigh the pros and cons of eating locally grown foods and share their new insights into the issues surrounding where there food is grown and how it is travels to their plates, many things which we take for granted every day. There is also the difficult question o how we should weigh our options: for example, choosing between foods that are delivered fresh but may have been grown far away, and those which were grown locally but require the use of scarce resources like water in dry climates or heat in cold climates. While students may not be “converts” to eating locally grown produce, it will bring it to their attention and make them more aware of the chain of labor and travel and the decision making that goes into getting food to their homes.