Heather Singler
Southwest Miami Senior High School
Kampong APSI – Summer 2015
The Miles on Our Table
Grade Level: 10th
Objectives:
Students will be able to explain the concept of food miles.
Students will be able to compare and contrast local, regional, and global food systems.
Standards:
Duration:
2 hours
Materials:
Internet access
Calculator
Map of the World
Vocabulary:
Food mile - a measure of the distance travelled from point of harvest to where the food
is ultimately purchased or consumed
Local food system - where much of the food is sold directly from farmers to consumers
through local farmer’s markets or community supported agriculture
Regional food system – where food is sold within the state it was harvested
Global food system – where national and international food is imported and sold to the
consumer indirectly
At a Glance:
This activity is designed to engage students in discovering different food systems and
where the foods they consume are harvested. In this lesson, students will explore the
concepts of food miles by calculating the miles travelled by the items in their breakfast.
Students will then compile a list of items sold at a farmer’s market and use these items
create a meal using only locally grown foods.
Background Information:
In the field of consumer food choice, there have been several recently growing trends
including, organic and locally grown foods. Consumers are now taking closer looks at
how foods are grown and where they are grown. Some of this trend can be attributed
to issue of food miles and transportation energy use. To better understand this trend
we need to first need to define the difference between local, regional or global food
systems.
Food systems include the inputs and outputs of packaging, transporting, marketing,
consuming and disposing of food and food packages. We can categorize food systems
into local, regional and global. Local food systems are where much of the food is sold
directly from farmers to consumers through local farmer’s markets or community
supported agriculture. Regional food systems are based on existing state distribution
and are generally transported by semi-trailers and mid-sized trucks. Global food
systems include foods that are supplied by national and international sources (Wilkins
and Earnes-Sheavly, accessed 2015).
Tied into the distinctions between these food systems is the concept of food miles.
Food-miles is a measure of the distance travelled from point of harvest to where the
food is ultimately purchased or consumed. The increased focus on food miles has come
with the increased use of global food systems and with growing concerns over climate
change. As we increase our consumption of international foods, we are increasing our
use of energy and subsequently increasing our emissions of greenhouse gases. In the
United States, globalization of food has increased the total food miles travelled from
1997 to 2004 by 25% (Weber and Matthews, 2008).
Preparation:
Prepare copies of student worksheets and maps.
Secure access to the Internet.
If possible, set-up field trip to a local farmer’s market.
Procedures:
Food Miles and Food Systems
1. Display several items of food. Ensure you display has at least one item that is
from a local, regional, and global food system. Ask students to choose which
item travelled the longest distance to be here today.
2. Use the food items on display to explain to students the difference between
local, regional and global food systems.
3. Tell students they will now be calculating the miles travelled in their breakfast.
Have students list all the ingredients found in their breakfast in their data table.
Students may need access to the internet to research the ingredients of their
breakfast.
4. Have students research where these ingredients may have been grown and
harvested. Tell them to consider the season for these ingredients when trying to
identify where these ingredients may have been grown. If students consumed
non-plant products, direct them to also consider where the grain used to feed
the animal may have been grown.
5. Provide students a world map. Ask students to plot and label on the map where
each ingredient was grown. Then have students use a colored pen to draw a line
from each ingredient to their city on the map.
6. Direct students to use an online distance calculator to gather data on the
distance travelled from harvest to their breakfast plate. Have them record the
distances for each ingredient in their data table.
7. Have students add up the total miles from their breakfast. Tell them that the
typical food travels 1500 miles and ask them to compare their breakfast food
miles to the average food miles.
8. Ask students to use their miles information to categorize their ingredients as
either local, regional, or global and add this information to their data table under
the Food System column.
Food System Energy Comparison
9. Tell students that they will now create a breakfast only using items from a local
farmer’s market. For this, you may either set-up a field trip for students to
attend a local farmer’s market, have the students attend on their own, or have
students research online the items sold at a local farmer’s market.
10. Have students now calculate the food miles of their locally grown breakfast by
repeating steps 3, 4, 6 and 7.
11. Ask students to calculate the difference in miles travelled between their ‘normal’
breakfast and their locally grown breakfast.
12. Next have students calculate the percentage increase in miles travelled between
their ‘normal’ breakfast and their locally grown breakfast.
13. Have students bring create and bring in their locally grown breakfast.
14. Discuss with students the benefits and drawbacks of locally grown food. In your
discussion, make sure to talk about energy use, availability, and sustainability of
food systems.
Assessment:
In their science journals, have students respond to the following:
1. Describe an environmental benefit and an environmental consequence for one
type of food system. (Answers below:
a. Local food system:
i. Benefit - less energy used to transport
ii. Consequence - more pesticide and fertilizer application to grow
plants not adapted to local conditions.
b. Regional food system:
i. Benefit - less pesticide and fertilizer application as plants are
grown in regions more suited to them
ii. Consequence – higher energy use and carbon dioxide emissions as
compared to local food system
c. Global food system:
i. Benefit – high diversity of foods that may be consumed
ii. Consequence – large amounts of resource utilized to transport
foods)
2. What changes would you like to make to how you participate in the food
system? Why? (Answers will vary but should reflect a move towards shifting
diets to locally grown foods that are in season to reduce food miles and energy
use.)
Extensions:
1. Create a school garden to explore further the benefits of local food systems and
farmer’s markets. Have students plan, plant, manage, and harvest a garden.
Have students decide if harvest may be used in school lunches, distributed
amongst themselves, or sold at a local food market.
2. Explore various modes of transportation and have students calculate how much
energy was used and how much CO2 was released with the transportation of
their breakfast items. Here is a great activity from Cornell University
Cooperative Extension and Department of Horticulture:
http://blogs.cornell.edu/garden/get-activities/signatureprojects/discoveringfoodsystems/.
3. Explore the concept of virtual water and have student calculate how much water
was transported with their breakfast items. Here is a great activity from Toronto
and Region Conservation: http://www.trca.on.ca/dotAsset/95898.pdf
Resources:
Discovering Our Food System: Experiential Learning and Action for Youth and Their
Communities. Retrieved from http://blogs.cornell.edu/garden/get-activities/signatureprojects/discoveringfoodsystems/.
Weber, C. L. and Matthews, H. S. (2008). Food Miles and the Relative Climate Impacts of
Food Choices in the United States. Environmental Science Technology. Retrieved from:
http://psufoodscience.typepad.com/psu_food_science/files/es702969f.pdf
Wilkins, J and Earnes-Sheavly (Accessed July 30, 2015. Lesson 3: Think Globally, Eat
Locally. In Discovering the Food System: An experiential learning program for young and
inquiring minds. Retrieved from: http://www.discoverfoodsys.cornell.edu/index.html
The Miles in Our Food
Data:
My ‘Normal’ Breakfast
Item
Food System
Miles Travelled
Total Miles Travelled:
My ‘Locally Grown’ Breakfast
Item
Food System
Miles Travelled
Total Miles Travelled:
Calculations:
1. Difference in miles travelled between your ‘normal’ breakfast and
your locally grown breakfast.
2. Percentage increase in miles travelled between your ‘normal’
breakfast and your locally grown breakfast.