We got the original idea from the cross in this great post at Easy Breezy Sunday School and then added a few little twists to it :-)
We wanted the children to think about God being a provider (linked to the Lord's prayer and 'give us today our daily bread') and to know that God wants good things for us.
My friend Charlotte built an amazing cross out of cardboard tubes of various sizes and spray painted it gold to make it extra special. In each of the tubes we put a sweet and then we asked the children to write or draw their asking prayers on a piece of paper, put it into one of the tubes and take a sweet as a reminder that we can ask God for things and that He wants to give us good things. We have done quite a lot of work with the children at the school and they are really familiar with the symbol of light to represent Jesus as the light of the world. Because of this we also gave them some battery operated candles to put into the tube with their prayer as a symbol of who they were bringing the prayer to.
When we went back a few days later for another meeting, the teachers told us that the children were still talking about what they had been doing!