Don't feel that as the teacher you have to do all of the talking. This can bore students and actually prevent them from learning. Allow your class to discuss ideas, brainstorm for possible ways of applying the lesson you are teaching to their lives, and come up with possible solutions for overcoming real obstacles that may prevent them from practicing the lesson in their daily living. Create some time during your class for brainstorming and discussion. Sing every opportunity you get with your students.
Kids tend to practice ninety to ninety-five percent of what they say and do.
So, singing is an excellent way of teaching your students something you want them to learn. Have your kids listen to the song the first time through, and then have them sing along the second time, and include any kind of physical movement to your songs like clapping, snapping, whistling, etc. Singing is one of the ways that they can actually say and do something at the same time and they'll tend to practice more frequently what it is that you are trying to teach them. Every class has behavior problems, including Sunday school classes. The best way to handle these problems is to prevent them from happening in the first place.