The lunches they serve at school are expensive and not very tasty. My kids have complained about them for years, actually I complained about them when I was in school too. But lunch kits are expensive and not very filling especially for teens. So I have found a few ways to save money on school lunches.
These I mostly figured out through trial and error, and may not work for your kids but you can take the idea and adjust it for your children.
Make sure the meals are balanced. It isn't doing either of you any good if they don't get the right mix of foods. Too many carbs and they will crash in class in the after noon. Too much protein and they will not have any energy for recess or changing classes. Too much sugar and they will be bouncing off of the walls. I try to make sure there is protein, grain, and a veggie of some sort every day. It is usually a sandwich, chips, a bottle of juice, some pudding or a fruit cup, and a cookie. That way they get 2 grains (2 slices of bread), protein (lunch meat or peanut butter), chips or carrots, a fruit(juice and fruit cup) and a dairy(pudding). My daughter also gets a tea bag since she has a teacher who allows them to drink either coffee or hot tea in class as long as they contribute to the supplies.
Now as to ways to make this meal less expensive. I buy the bread at the discount store. We have a really good one that sells Sara Lee breads for about 70 cents a loaf. That means that I can get the whole grain wheat bread for about 1/4 of retail. I stock up when I go and put it in the freezer until it is needed.
The lunch meats I make my self. I have posted before about making ham and salami. I also made a LOT of jams this summer so I can buy generic peanut butter for inexpensive sandwiches. Adding cheese to the sandwiches will add another dairy to the mix. Lettuce will add another veggie.
The chips I buy in big bags from the Dollar store or Big Lots and put them into sandwich sized zip top bags. That way they actually get more chips than are in the little individual serving bags, and I spend a LOT less for them. I can get about 6 lunches from an average sized (10-12 oz) bag that I pay about a dollar for. That is about 17 cents a bag instead of 30 or 40 cents for the little prepackaged ones.
The juice is another big savings. Buy a couple of single serve (8 oz or so) bottles with the screw on lids and refill them. You can find some sort of juice on sale just about all the time to refill the bottles with, and a 64 oz bottle will fill 8 - 8oz bottles at a fraction of the cost of buying new each time. Or you can refill with water, Kool-Aid, tea, lemonade, what ever. If you freeze them the night before, they will help keep the lunch cool until time to eat and still be thawed in time for lunch.
Pudding is another saving. Make your own. Invest in a couple of small (1/2-1 cup sized) containers from the dollar store. And some plastic spoons. These can hold fruit, pudding, a slice of last night's cake, what every you want to put in them. If you use them for fruit, I would suggest that you drain all of the juice out first in case the lid leaks. You don't want your bread to taste like soggy peaches. Don't buy the individual servings. You wind up paying for packaging and don't even get a full sized serving of fruit since they are mostly juice.
The cookies, again, you can make your self. or make brownies. These can both be made up and stored in the freezer in individual serving sizes. If you can keep the kids out of them after school.
You have to make sure your kids understand that ALL of the plastic comes home every day. Spoons get thrown away a lot. This is easier with lunch boxes, but my kids want paper sacks. My son had his lunch box stolen twice last year so paper sacks it is. And I can draw little pictures or sayings on them. Weird I know, but hey, they are still my kids and I like to make them smile. OR groan. Or, hehe, be embarrassed by silly stuff on their lunch bags.
Is it really cheaper to brown bag a lunch rather than eat in the cafeteria? If you consider that their lunches are about $2 a day, and they will not eat all of it or in some cases even most of it, I would say that it is. You know that they will eat what you give them since they get to help you shop for it and you will know that they are eating right. It is also nice to know that you are teaching them that they do not have to buy a lunch every day when they get to college or in the workforce. This is a money skill that is highly overlooked these days. The less money they waste, the less they will need from Mom and Dad.