Another time saver that we used to do was to pre-wrap the snacks for the kids lunches. I would put the chips, crackers etc. in individual size amounts in sandwich bags and put them into a large plastic container with a lid. The kids made their own sandwiches on the weekend and put them into the freezer. Each child has their own type of container. One has a square container, one has a round one and one has a butter container.
Each night the kids would pick a snack and put it in their lunch box. In the morning I add the sandwich and the juice box. Some mornings as we are about to leave, we realize that we didn't pack any lunches. Since everything is pre-done, we can get the lunches together as we leave. I don't pre-wrap the snacks anymore. Each of the kids likes to do their own.