Self-control is the iron in obedience. It's the strong walls which protect us from sin. It gives godliness its backbone. Without self-control, we are floppy, easily influenced, vulnerable. With self-control, we learn to deny our sinful desires, and to use our thoughts, words and actions to serve God.
The children and I talked about what temptation means (wanting to do the wrong thing, or other people wanting you to do the wrong thing) and what self-control means (saying "no" to temptation).
I showed the kids four props: a magic plate which produces any food you like on demand, a magic wand which gives you the power to do anything, a treasure chest full of gold coins, and a crown. I asked, "What would you say if someone offered you these?" and "Would it be easy to say 'no' to them?"
Then I shared the story of Jesus, who resisted exactly these temptations at the outset of his ministry. Who fasted for 40 days in the wilderness, and was tempted by Satan to use his powers for his own ends, to turn stones into bread. Who responded with the words, "'Man does not live on bread alone, but on every word that comes from the mouth of God" (Matt. 4:4).
Who was taken by Satan to the highest point of the temple, and challenged to jump down so that everyone would see God's rescue. Who chose instead to obey God's Word, "Do not put the Lord your God to the test" (Matt. 4:7). Who chose the path of weakness and service instead of attracting followers by showing off his powers.
Who was taken by Satan to a high mountain, and offered all the peoples and riches of the world if only he would worship him. Who obeyed God's command to "Worship the Lord your God, and serve him only" (Matt. 4:10). Who refused to establish an earthly kingdom, choosing instead to die on the cross that we might live.
The kids knew the story of Jesus' temptation well, and enjoyed capping me at every point ("And then Jesus said ...!"). We talked about the times we might need to exercise self-control: when tempted to be greedy, to hit someone or speak angrily, to look at inappropriate TV shows or internet sites, to lie or take something that's not ours.
"Like a city whose walls are broken down is a man who lacks self-control" (Prov. 25:28). Our craft was a door-hanger, a way to say "Keep out!", the child's version of the city wall. On one side was "Stop! Think! Obey!" in traffic-light formation, and on the other side the verse "Let us be alert and self-controlled" (1 Thess. 5:6).