A stewardship game
The Colander Game
(which is really an object lesson disguised as a game)
Probably a good idea to play this one outside. 
First set up the demonstration as a relay race. Give each team a plastic colander. They try to fill it as fast as they can from one bucket (using a ladle or cup) and move the colander of water to another bucket three feet away. Of course, the water will pour through the colander! (this is the first teaching point).
Now label the first bucket "money" and take one of the collanders and begin labeling the holes in the colander as "things to spend money on." [Purchase plastic colanders at the dollar store so you can write on them with a sharpie to label the holes with all the things people spend their money on.] Once labeled, have the kids 'demonstrate' how their ladles of money keep going through all the holes back into the bucket. (Talk through the meaning of this.)
Now switch the colander and water metaphor to "TIME," and on the second colander begin writing "things we spend time on" based on what the kids tell you. Some of them are wasteful for sure. Have them demonstrate the water pouring through this colander once again.
Ask.... In our game, how do we get time and money (the water) over into this second bucket?? The answer is to start covering up the "holes" that cause us to waste time and money.
Give each team some paper towel (which they will soon use to line their colander with). Ask them what the "paper towel" represents... i.e. what can a person do to STOP WASTING time and money and get it to God's bucket. Write some of these things on the paper towels and then place them in the collander. Sprinkle with water to get the paper towel to conform to inside of the colander where it will seal the holes and allow the colander to hold water.
Then label the second bucket "GOD'S PRIORITIES" and have the students come up with suggestions for what they think God's priorities are. Look at Matthew 6:33, Seek First the Kingdom, and discuss what Jesus' priorities probably were.
Finally, now that you have everything labeled (colanders, papertowel, buckets), play the game one last time to see who can get the most water into God's bucket within 1 minute.
