What is a good desalinization science fair project?

Answer 1

Make a simple set-up like this:

1. Put salt water into a bucket.
2. Place a smaller weighted container in the midde of the bucket to catch the freshwater.
3. Drape a sheet of clear plastic over the top of the bucket and push the center of the plastic down to make a good "drip zone". Put a small rock in the drip zone dent to hold it down.
4. Set the apparatus in direct sunlight. Water will evaporate, condense onto the plastic and drip into the catch container.
5. Plan a variable to test. If the basic set-up described above is your control set-up, then your experimental set-up might be one of the following:
-- wider bucket
-- shallower bucket
-- sheet of glass or plexiglas over the plastic (I think that's a good idea because it will make the inside of the bucket get a lot hotter).
-- insulation on the outside of the bucket

Good luck. Now I feel like trying this myself.

Answer 2

A little tent that catches evaporated water and drips it into cups, like something you would build if you were stranded at sea.