As parents it's our duty to teach our children about God and teaching them how to pray is teaching them the basic of knowing and worshiping Him. Prayers is our means of communicating to God and it must be something that comes from our hearts and mind. Here's the Five Finger Prayer guide on teaching our child on what to tell God.
Thumb (people who are close to you) These are your close friends and family, often the first you think about when you pray. Give thanks to God and ask his protection on your parents, siblings, friends, and classmates.
Pointer (people who point the way) These are leaders in your life, such as teachers and pastors. Offer God your thanksgiving for them and ask him to help them in their important work.
Tall Finger (people in authority) The big people in the world need prayer too. Ask God to give wisdom to our government, military, and police.
Ring Finger (people who are weak) This is your weakest finger. We should remember others who are sick, live in poverty, or are treated badly. Pray that Jesus would give them new strength.
Little Finger (your own needs) God wants to hear your needs too, especially when you put others first. Pray for your own growth in mind, body, and spirit.