During my school's Heritage Fair this year, students had the opportunity to do an audio scavenger hunt (in French as we are a French Immersion school). Two classes (Grades 3/4 and 4/5) had the opportunity prior to the fair to script and record podcasts about their projects. They were then asked to compose a question that could be answered by listening to their podcast. I posted the completed podcasts online and provided the students with a question sheet to guide their scavenger hunt through the podcasts. Students really enjoyed this activity during our Heritage Fair and I would definately look into doing it again during next year's fair!
Our Heritage Fair Podcast Website (in French): WWHF Blog
The document used by students to complete the audio scavenger hunt (in French):