A few more cooler tricks: Drain and top off all your coolers just before launching filling all the open areas between blocks and jugs with cubes. Designate some coolers to be not opened at all for the first three days. Only open these coolers once a day to remove ice to supply food and drink coolers. Use small coolers for beverages so the larger coolers don't have to be opened frequently. Freeze your food so that it act's like ice, I even freeze sticks of butter. As your ice melts do not drain the water till it warms enough to be useless, the slighty cool water can serve to pre-cool warm drinks before they are put into your precious remaining ice, I usually do this in the evening. As the trip progresses double wrap your trash and store it in the coolers as you empty them, put the bungy cords back on. If you do every thing just right you should have cool drink on your last day.
Another suggestion would be to envolve the scouts in the menu planning. One of the few useful things I took from my scouting experience is meal planning. To this day I write out a menu for every trip. I'd guess the kids would be less likely to complain about the food if they have a say in what they are eating.