When kids are young, getting them to go to Sunday school isn't too tough. Stickers and a snack can usually entice them to class. However, teens are tougher to convince. If you want to attract teens to Sunday school classes, you might need a more creative approach to get them to willingly attend.
Talk to the teens in your church who are possible candidates for Sunday school classes. Ask those who attend regularly why they do so. Some likely go because their parents make them, but for those who are there voluntarily, ask them what about the class appeals to them. Find out from those who don't attend, why they don't -- and what might make Sunday school more attractive to them.
Make the message relevant. Teenagers often dismiss the Bible and its teachings as outdated and not relevant to their lives today. Whether you use a prepared curriculum or develop your own Sunday school lessons, present the message in a way to which teens can relate. This doesn't mean just using modern language, or diluting the message. Rather, this involves connecting the choices and challenges teens face today with those faced by familiar Bible characters. For example, Ask the teens if they ever feel peer pressure and discuss what that's like. Then relate a Bible story to the discussion such as how Daniel and his friends showed amazing courage by standing up to King Nebuchadnezzar.
Change it up. Even for the kids who choose to come to Sunday school, a straight hour of lecturing isn't very appealing, so it's likely a real turn-off that for the ones who don't want to be there. Intersperse your teaching with occasional videos, humorous anecdotes, music or other means of conveying the message beyond lectures. Involve the kids in the class by having them develop or act out modern versions of Bible stories or role-play situations. Follow up a series of lessons with a game show-style, friendly competition to test the kids' knowledge of what they learned.
Vary the location. Kids sit in classrooms in hard chairs at metal desks or wooden tables all week long. Sunday school won't appeal to most teens if it's viewed as just one more uncomfortable, boring class. Set up the Sunday school room with some pillows or comfy couches and chairs. In good weather, go out to a nearby park and have your class in the grass under a shade tree. Consider meeting in a cozy coffee house or in someone's home for variety. Such locations might help put teens more at ease and are often less off-putting than a standard classroom setting.