I found an unopened box of crackers in my kitchen cabinet the other day that I bought a few months ago to set out with cheese if we ever had unexpected guests come over. They are Carr's Whole Wheat Crackers, and although they have slightly over 4 ingredients (I don't have the box anymore, but I believe there are only 6 or 7 ingredients), they are an excellent substitute for cookies. They are twice as thick as a normal cracker and also crumble when you bite into them. They have a touch of sweetness but aren't too sweet. Mason loves them and I'm sure any child wouldn't know the difference between these crackers and cookies, unless of course you feed your child a lot of sugar loaded food.
I know this is a processed food, but I purchased them prior to making my new year's resolution; and I think these are a good option if you want a quick child friendly snack and find yourself in the cookie/cracker isle at the grocery store.