Water
One of the first things you probably learned in elementary school science is that “water is necessary for life.” Just because you are now driving your own kids to elementary school does not make this maxim any less true. Water is essential for survival, but contaminated water can be deadly. If the power is out, a pipe bursts or a water main is somehow contaminated, you need to have drinkable water on hand. According to FEMA, an emergency supply kit should have water for at least three days and allot one gallon or four liters of water each day per person. A family of four, then, should stockpile at least twelve gallons or 16 liters of water.
If you know a serious storm or other potential emergency is approaching, you can also add to your emergency water supplies without leaving home. Fill up any empty water bottles or stock pots, and fill the bathtub. These last minute additions could make a great deal of difference in an emergency.