Get an audience together and learn how some sewage plants use sewer lice to clean sewage water.
* Transparent container
* Mountain Dew
STEP 2: Fill the transparent container halfway with "sewer water" (Mountain Dew).
STEP 3: Drop several "sewer lice" (raisins) into the sewer water and observe.
Your audience will eventually realize what's floating inside the Mountain Dew is not sewer lice. Inform them that once enough carbon dioxide bubbles in the Mountain Dew collect on the sides of the raisins they "swim" to the surface. Once at the top, the carbon dioxide bubbles pop and the raisins "swim" back to the bottom. Inform your audience that sewage is cleaned at a sewage plant through one, two or three stages and not sewer lice.
Jason Lindsey is a science outreach educator with Hooked on Science. Check out his website www.hookedonscience.org for webcasts and experiments that might get you hooked on science.