This engaging and interactive "Choose Your Own Adventure" PPT highlights the famous conflict between Pope Gregory VII and the Holy Roman Emperor, Henry IV . Students play the role of Henry and choose how to respond to the Pope's actions, including his declaration of supreme authority. There are various outcomes that can result depending on which path your students take. Only one route reflects what actually occurred historically. Students will have fun trying to figure out what the correct course of action is. Overall, it's a good lead in to the topic of Medieval Conflicts.
Also, check out Charlemagne: Convert or Die - Choose Your Own Adventure