Sharing is a wonderful thing to do, and it is something that is SOOOOO difficult to teach the kids. But my trick is, I tell them: When you share, you get more!
How does that work: You see, whenever I tell them to share, I will give them more than if they were not sharing. Example: If I am giving out chocolates - each will get a piece. But if they are going to share, they are given more, with the extras going to whoever they are sharing with. In the end, whoever they have shared with will share their own loot back with them (whether immediately or later)- so they end up with more than that one piece I would have given them in the first place.
This seems to be working. So my kids dont find it that hard to share. In fact, they seem quite happy to share.
Sharing has also been working for me. I have recently been sharing recipes with some friends. As these friends are 1st time bakers, I share with them the easier fail-proof recipes. You know what? After they have tried out the recipes, they set aside some for me to try and for comments!! See by sharing recipes, I get free cakes. Not bad, huh? So it's true : When you share, you do get more!! Only problem is: now I have more to fit into those jeans of mine!!