- Plastic cup, 1" shorter than sides of bowl or cut to size
- Clear plastic food wrap
- Tape or rubber band large enough to go around bowl
- Small rock or weight
- Salty or colored water
- Put salty or colored water in the bowl.
- Place the cup in the center of the bowl.
- Stretch clear plastic wrap over the top of the bowl and secure with tape or a rubber band.
Make sure the seal is tight and no air can escape.
- Place a weight on the center of the plastic wrap above the cup.
Press down slightly on the plastic wrap so it stretches and sags down over the cup.
- Place the solar still in full sun.
- Observe what happens.
- After some water collects in the cup, taste it.
- Is the water clear?
- Does it taste salty?
- Why does the water taste different that tap water.