If you want to teach your children not only about prayer, but to pray, then you will have to live a life of prayer yourself in class and out of class.
Be sure that prayer has a prominent role in your class or club. Open and close in prayer, give time during the class for the children to praise, thank and ask God in prayer.
During the week pray for the children by name. Send a postcard to each child occasionally saying that, “Today, I prayed for you.”
The children will begin to get the idea that prayer is not only something you believe, but something you do.