Science fair thinking

Background review…
http://www.lifespy.com/2007/how-to-cook-spaghetti-noodles-al-dente/
1. Adding salt and oil
For the above-mentioned 500 grams and 4 liters, 2 tablespoons of salt is needed. Salt ensures that the pasta will cook evenly. A word of warning though, salt raises the water’s boiling point so better add it once the water boils and not before.
Adding oil to the boiling water will prevent the pasta from sticking. Also, you can toss the pasta once in a while with a pair of tongs or chopsticks.
http://www.wonderhowto.com/how-to/video/how-to-cook-pasta-al-dente-283433/
Step 2: Add salt and boil
Add a tablespoon or two of salt per every five quarts – depending on what your personal diet allows – and bring the water to a boil.

Homemade Ice cream
http://crafts.kaboose.com/ice-cream-in-a-bag.html
What you'll need:
• 1 tablespoon sugar
• 1/2 cup milk or half & half
• 1/4 teaspoon vanilla
• 6 tablespoons rock salt
• 1 pint-size plastic food storage bag (e.g., Ziploc)
• 1 gallon-size plastic food storage bag
• Ice cubes
How to make it:
1. Fill the large bag half full of ice, and add the rock salt. Seal the bag.
2. Put milk, vanilla, and sugar into the small bag, and seal it.
3. Place the small bag inside the large one, and seal it again carefully.
4. Shake until the mixture is ice cream, which takes about 5 minutes.
5. Wipe off the top of the small bag, then open it carefully. Enjoy!
Tips:
A 1/2 cup milk will make about 1 scoop of ice cream, so double the recipe if you want more. But don't increase the proportions more that that -- a large amount might be too big for kids to pick-up because the ice itself is heavy.
Salt water doesn’t freeze as easily
Salt melts ice
http://antoine.frostburg.edu/chem/senese/101/solutions/faq/why-salt-melts-ice.shtml