The go to recipe for most people who want to cook with their children is chocolate chip cookies (or cookies of any kind). Why not try something a bit healthier and easier? Cookie dough often involves a mixer and the dough can be quite stiff (too stiff for little hands). In addition, if you're making cookies that you plan to roll out and decorate, you have to chill the dough--definitely DELAYED gratification. Instead of, or in addition to, the ubiquitous chocolate chip cookies, try one of the following recipes:
"Spiced Tea": sometimes this is called Russian tea. It's mostly Tang and sugar; no wonder kids love it! It's easy enough for a young child to stir together and fairly instant gratification if you already have some hot water on hand. Mmmm.... Perfect for a cold, rainy day.
When first starting out with actual cooking/baking, particularly if your "helper" is a very young child (2 or 3), try the Whole Wheat Applesauce Muffins. There are no eggs, so if your young helper licks the spoon frequently, it won't matter (personally, I don't have much issue with licking the spoon even when there ARE eggs present, but I suppose I can't advocate that). This batter is exceptionally easy to whip up, easy to measure, easy to stir, and, unlike most muffin batters, can't really be overmixed. And they are YUMMY!!!
"Jiffy" Cornbread Muffins are another good place to start. Fairly straight forward and your child will be immensely pleased to have helped make part of dinner. This batter, made as cornbread, is easy enough for an elementary school-aged child to do by him- or herself, if he or she is familiar with the kitchen. Unlike other cornbread recipes, it does not require buttermilk, nor does it require a hot pan already greased with hot butter/grease (making it safer for a child to handle).
Stir and Drop Sugar Cookies are an easy cookie recipe to try. They don't require chilling or a mixer. They can be decorated easily with sprinkled (always a hit with kids!).