In an effort to help your folks know the Bible more clearly, consider this learning tool, 30 Days to Understanding the Bible in 15 Minutes a Day. This is ideal for the new believer, but would certainly be a great refresher for anyone!
While not exhaustive, or overtly complex, this straightforward plan gives a brief way to broadly help folks grasp the scope of the Bible. There is a format for a teaching setting, and there are also great bonuses like a guide for telling the story of the Bible in 1000 words.
This resource has been a blessing during our Equip University classes.