I just read a study that supports the idea that some of us can't waste. They gave undergrads four 100-calorie packages of crackers or one 400-calorie package. The students ate fewer crackers when they got the smaller packages.
The average students ate 25% less, but the obese students ate 50% less!
Some of us just have a habit of finishing things.
Knowing this, the solution is to portion food out into smaller containers. Take a yogurt, put half in a dish or another yogurt container, and put the rest away for later.
For me, a huge breakthrough was choosing NOT to clean the kids' plates - deciding not to be a walking rubbish bin.
I note that my husband hasn't cracked that yet - he complains that I put too much food on his plate when he's trying to lose weight, but the habit of cleaning his plate is too engrained.
I just hope that I haven't passed the urge on to my kids, as my epiphany happened about half-way through their childhoods.
Nicky.
Having a compost bin helps a lot. You feel the food isn't being wasted. I suppose having a pig would serve the same function, but this is frowned upon in most apartments and suburbs.
In your family, perhaps the solution would be to start everyone off with very small portions, knowing that they could have seconds if they liked. Maybe your children would adopt that pattern in their own homes.