High School Food Safety Lessons
1 Understanding Bacteria
Health Education Standards
(grades 9-11) 1:1; 3:1; 6:3
- Introduce this lesson: (modify according to
lessons to be taught)
“Food safety is a very important issue that we will be pursuing for
this lesson and the four that follow. Essentially, food safety
is everyone's responsibility — everyone involved in growing,
processing, transporting, and handling our food along all the
points in our
complex food distribution system. Food safety is a serious issue
the wellbeing of every individual. We all must eat so we are
all at risk of becoming ill if our food becomes contaminated.
we will begin by understanding that food safety has to do with
bacteria. First, we must learn where bacteria come from and how
they grow, then how we can control bacteria.”
“Let's get started. We have a great
deal to cover to begin our understanding how to keep our food safe.
I want you to remember the points we make
in this lesson. Remembering could truly affect your life.”
- Ask the students to divide into four teams
and to select a spokesperson to report on the following:
- Where bacteria live and how they grow.
- How bacteria survive
- How to control bacteria growth in foods.
- How scientists can
tell good bacteria from pathogens.
- Provide Team 1 with page 12 in Science and Our Food Supply:
Investigating Food Safety from Farm to Table: Teacher's Guide
for High School Science Classroom. Provide Team 2 with page 13;
3 with page 14, and Team 4 with page 14. Ask that the reports
be lively and create understanding.
Give students 10 minutes to prepare an outline for their spokesperson.
- Ask the students if they understand the reports and clarify
|Time to Tune In
Module 1—Understanding Bacteria
- Introduce the video by explaining:
“There’s a lot of science behind keeping our food safe. Let’s
begin by meeting Dr. X, a crusading food scientist who’s
dedicated his life to fighting harmful bacteria and foodborne
illness, and Tracy, a student working on her science video
teams up with him on his mission.”
- “I challenge you to uncover the
following food-safety science links as you watch the video:
What four weapons does Dr. X use to fight harmful bacteria?
- What is the significance of the mysterious
- What is Dr. X referring to when he talks
about the “baddest
of the bad?”
- What does DNA have to do with bacteria?
What does it tell us?”
- Show video Module
1—Understanding Bacteria (Time: 15
- “Dr. X talked about his four food safety weapons for fighting
harmful bacteria; what are they?” (Clean, Cook, Chill,
and Combat Cross-Contamination)
- “What’s the significance of 0157:H7?” (E.coli
0157:H7 is one kind of E.coli that causes foodborme illness.
E.coli evolved from the harmless E.coli bacterium.)
- “Dr. X described the “baddest of the bad;” what was
he referring to?” (The 12 Most Unwanted Bacteria that cause
- “What does DNA have to do with bacteria?” (DNA encodes
the information that enables bacteria to grow, reproduce, and
- “What does DNA tell us?” (When there is an outbreak of
foodborne illness, epidemiologists use the pathogen’s DNA
fingerprint to determine the source of bacteria.)
- “What does science have to do with food safety?” (Food
safety has everything to do with controlling bacteria. There
are all kinds of scientists dedicated to developing methods to keep our food
- “Whose responsibility is it to keep our food supply safe along
the Farm-to-Table Continuum?” (It’s everyone’s
- “What effect do each of the 4Cs have on bacteria?” (Cleaning
removes bacteria from hands and surfaces. Cooking [heat] kills bacteria
by breaking down their cell walls. Chilling slows down the bacteria’s
metabolism, thus slowing their growth. Combating Cross-Contamination
prevents the spread of bacteria from one object to another.)
- Invite students to ask questions related to the video Module
1—Understanding Bacteria. Refer students to sources related
to their questions, if you do not know the answers to their questions.
- Use the following exercise to emphasize how
prevalent foodborne illness is and to help students realize the seriousness
of this issue and how it is related to them.
- Ask students:
“How many of you have been affected
by foodborne illness?”
Write that number on the board.
- Now compute what percentage of the class thinks they have
had foodborne illness.
- Using that percentage, ask your students to estimate how many
students in the entire school might have had foodborne illness.
(Note: Tell the students that this is only an assumption, and not
survey. This information is simply to help the
students relate to the statistics that you are about to give them.)
- Point to the information already on the board regarding foodborne
“There are approximately 274 million
people in America. If 76 million people become sick due to foodborne
illness, ask the students
to calculate the percent of the population affected. Discuss the students'
reactions to this percentage and have them relate it to the
percentage calculated for the class. Then reiterate the importance of studying
|Summarize by saying:
It now becomes clear that bacteria are everywhere--we learned they
grow, survive, and reproduce. It is possible to control pathogenic
bacteria in food by using the 4Cs: Cooking, Chilling, Cleaning, Combating
Cross-Contamination. The essence is that it is everyone’s responsibility
to control the spread of bacteria—from farmer, food processor,
persons who transport the food, people who work in markets and restaurants,
to those of us in this room who eat the wonderful food supplied to
us from world-wide sources.”
|Ask the students to:
- Be alert to articles in the press related to foodborne illnesses
and to bring these articles to the classroom for posting.
the English Department to ask for essays related to food safety.
with the Science Department providing further study of food safety
by utilizing lab lessons found in Science and Our Food
Supply: Investigating Food Safety from Farm to Table: Teacher's Guide for
High School Level Science Classrooms.
- Check the Internet to learn
more about when and why food safety became a National Initiative.
Some Websites are: