Help the kids discover additional information about the Bible story, from dictionaries, concordance, maps. Look up texts that support the lesson objective or that apply the lesson. Throw in a quiz sometimes, the style-two learner will love it. Because they excel at it. Don't be tempted to tell everything you know on the topic, however.
Kids remember best what they discover themselves, and discovering takes time.
If the discovery of content began in the previous 15-minute segment, you can take time to discuss the meaning of what they learned and offer additional material.