Some of them may have had a bad experience with memorizing scripture when they were young. You may have a sales job ahead of you, -hence this first paragraph. View this as an opportunity to show others how the times, tools and attitudes have changed. Sometimes we underestimate our kids. It may be easier and quicker to edit new verses into the program yourself, or have a teacher do it, but let me suggest that you may be missing a wonderful education-memorization opportunity.
Adults view the keyboard and typing as work.
Kids do not. They view typing as a game. The typing of the verses is also a memory device. Those eyes and fingers are processing the scripture verses at a different location in the brain than simply hearing it would. This is why Sunday Schools use music, art and videos.