I try to always have fruit be a portion of the snack and the fruit is unlimited. So today we are having yogurt and apples slices. They all get 1 serving of yogurt, and then the apple slices are served family style and I will replenish them until everyone has had there fill. For the granola bars I'd only give them 1 of the 2 in a pack and then they could have as many orange segments/grapes/etc as they wanted. Crackers and cheese is one of the snacks that I don't always serve a fruit with and I will say they always want more of this snack than anything else.