My kids (4 boys) make their lunch for school every day with a sandwich, granola bar, fruit snacks, veggies, etc.
Even with the cheap school lunch prices ($2) we save money by having them make their lunch 4 days per week. Every Friday or Saturday we eat leftovers for dinner to clean out the fridge of whatever is left from dinners throughout the week. It would cost us a fortune more to eat out than to cook at home.