Science and Our Food Supply: Investigating Food Safety from Farm to Table

ADVANCE PREPARATION

• 

Prepare or order 3 sterile Petri dishes containing nutrient 

agar for each team of 3 to 4 students. You may want to 

order extra dishes for students to test additional areas. 

Note: Petrifilm

™

 dishes can be used instead of Petri dishes. 

See Resources on page 95. 

• 

Sterilize (boil) 500 ml of tap water for each team. You can 

boil the water in beakers and then cover with aluminum 

foil until ready to use. Students will use the water to wet 

swabs for testing dry surfaces. 

• 

Make one copy of the Lab Report Outline for each student. 

• 

Make one copy of the Bacteria Everywhere Data Table for 

each team. 

INTRODUCTION

As students walk into the classroom, 

be peering through a large magnifying 

glass in search of bacteria in various 

sections of the classroom. Your  

students will wonder what you’re 

doing. Explain to them: You’re going 

on a microorganism safari, and during 

this safari you’re going to become 

“science detectives.” Your assignment 

is to find areas where bacteria are living 

and come up with a plan to determine 

which areas have the most and least 

bacteria.