Challenge yourself and your family to eat every meal at home for an entire week. This includes breakfasts, lunches (packed and taken to school or work), and dinner, as well as all snacks and beverages (no Starbucks!) for an entire week. This challenge is more difficult than it sounds as it is almost automatic for many people to run by a fast food place for a meal, stop by a coffee shop at least once a day, and even use the vending machine at work if you didn't plan ahead and bring a snack.
This will not only show you what it is like to plan, shop for, and prepare a range of meals but it will give you a good idea of how much food it takes to feed the family for a week, the cost of said food, and what it would be like if you couldn't go to the store or go out to eat for an entire week after a disaster.
Be sure to prepare ahead of time by creating a menu, shopping for everything you need at one time, and getting together the things you need to pack each lunch (lunch bags, ziploc bags, thermos for coffee, etc). This will definitely be a learning experience!