Science Fair Connections
Just growing bacteria in a Petri dish is not a science fair experiment. Yes, it is gross and cool and fascinating, but it doesn’t meet the requirements of a science fair project. If you want to do a science fair project about germs, you have to add a variable, or something that changes in the experiment.
With the Bacteria Growing Kit, adding an anti-bacterial hand sanitizer is a variable. Make one dish of germs and one dish of germs with a drop of the anti-bacterial sanitizer or, better yet, make three dishes–one as the control (just germs), one with an anti-bacterial sanitizer, and a third dish with another brand of anti-bacterial sanitizer. Then you can see which anti-bacterial sanitizer is more effective in killing germs. Just make sure that all three Petri dishes have germs from the same place in your home or classroom so that you know they are all exposed to the same bacteria. They also need to be grown in the same warm, dark place for the same amount of time so that the conditions are standardized as much as possible.
Growing bacteria is such a popular activity that we’ve written it up as a sample science fair project (see the link below). The sample project describes the swabbing technique to collect the germs and gives you lots of helpful hints about growing bacteria. It makes suggestions about variables and gives you some ideas to make the project your own. What it doesn’t give you is the data. What fun would that be? Don’t you want to do the experiment for yourself and see what discoveries you make?
Other ways to make the Bacteria Growing Kit into a science fair project:
Examples of Independent Variables: (choose only ONE independent variable to test)
Start up question – Which door knob has the most bacteria?
Variations to the independent variable: bathroom door knob, your bedroom door knob, your front door knob
Start up question – Which mouth is the cleanest?
Variations to the independent variable: your mouth, your mom’s mouth, your teacher’s mouth, your dog’s mouth
Start up question – How clean does my mouth really get?
Variations to the independent variable: no brushing, brushing, brushing and mouth wash OR test different toothpastes – before brushing/after brushing with Colgate, before brushing/brushing with Crest, before brushing/brushing with Arm & Hammer, etc.