A Science Fair Project With Bacteria

Comparing bacteria from common items is an interesting way to unlock the dirty little secrets of the world around us. Use your science project to educate those around you about just how much bacteria lies in common places.

Materials

This experiment requires several culture dishes, sterile cotton swabs, labeling device and a dark room-temperature place for storage. Culture dishes are round and should be filled with agar, which will provide a stable environment for your bacteria to grow in. Prepare your culture dishes by heating a bottle of agar and letting it cool slightly. Pour the substance into the sterile dish, covering about a half of the depth. Allow the agar to solidify.

Collecting Samples

Every experiment needs a control, so leave one culture dish empty; it will be used as a baseline for comparison. Use sterile cotton swabs to collect bacteria from various places such as the inside of your mouth, a water fountain, a stair hand rail, a door knob, a telephone, or the bottom of a shoe. Think critically about where you think bacteria may live. Rub each swab on a separate culture dish in a firm zig-zag; be sure to label immediately. Store in a dark place at room temperature.

Analyzing Data

Check on your culture dishes periodically. Take pictures of each swab in equal increments to track bacterial growth. After about two weeks, the project will allow you to identify which places hold the most threat of bacteria. The results may surprise you.

References

• Home Training: Bacteria Science Project Guide.