I'm a single mother to an 11 year old who eats pretty much nonstop... Or he would if I let him! hehe
I find that a single 2-lb bag of carrots and a single 2-lb bag of petite potatoes is enough starch and vegetables to go with our single servings of meat. Fills us up without wasting food or overdoing the calories... And one meal for the two of us has an average cost of -roughly- $5. Not bad, eh?
Now if my rent didn't take up half my income I could probably get more than 2 lbs of potatoes, 2 lbs of carrots and one bag of pre-mixed coleslaw a week to go with the meat we eat... But you make do with what you have and hope for the best. Unfortunately for me, I keep forgetting I'm supposed to be losing weight so I hit the 7-11 just up the road for their cheap junk food.