If you're not used to eating freeze dried foods, don't put that in your supply kit. Another good thing to put in is water. You need to have, for your family, one gallon of water per person per day. That's for drinking and food preparation, as well as sanitation. Other items could include batteries for the portable radio that you should have in your kit.
Flashlights are very important.
Any medication that your family may need, over the counter or prescription. Personal hygiene items, such as soap, toothpaste and brush. Also, a change of clothing. In a flood, that's very important. Your clothing often does not stay very dry.