Objective

By the end of this lesson, you will be able to understand the concept of the "five second rule" and conduct a science experiment to determine if it is safe to eat food that has fallen on the floor for 5 seconds.

Materials and Prep

Materials needed: a variety of foods (e.g. crackers, fruits, etc.), a clean floor surface, a stopwatch or timer.

Before the lesson, ensure that the floor surface is clean and safe for conducting the experiment. Also, gather the different types of foods to be used in the experiment.

Activities

1. Begin by discussing the concept of the "five second rule" with the student. Explain the idea that food dropped on the floor may be safe to eat if picked up within 5 seconds.

2. Conduct a demonstration by dropping various types of foods onto the clean floor surface and timing how long they are in contact with the floor.

3. After each food item is dropped, discuss with the student their predictions about whether the food is safe to eat based on the time it was on the floor.

4. Finally, have the student record their observations and conclusions from the experiment.

Eighth Grade Talking Points

• The "five second rule" is a popular belief that food dropped on the floor is safe to eat if picked up within 5 seconds. However, it is important to understand the science behind this idea.
• When food comes into contact with a surface, it can pick up bacteria and other contaminants. The longer the food is in contact with the surface, the greater the chance of contamination.
• During the experiment, we observed how different types of foods interacted with the floor surface and discussed whether the "five second rule" held true for each case.
• Based on our observations, we can conclude that the safety of food dropped on the floor depends on various factors such as the type of food, the cleanliness of the floor, and the length of time it is in contact with the floor.