Stock your pantry with $5 a week; you buy your usual stuff, but buy one type of food to put in the stockpile/pantry, and you can do it week by week and in a year you will have food and other supplies enough to cover your family in an emergency. She discusses different methods and how to save $ while doing it.
52 Prepper's Projects for Parents and Children
Both books are on Kindle and paperback, I have the first one, and it starts small since a little done consistently can help.