Part of the answer to this depends on how old your children are. Teens are hollow from the mouth down usually.
Small children eat less.
It also depends on what your family likes. If you have to toss food or give it away because they won't eat it, it's not frugal. Check out the marked-down meat bin if your stores have them. I frequently have gotten excellent savings on perfectly good meat doing this, just immediately freeze or cook it. I would suggest staying away from buying cold cereal if possible.