The Relative Risk of Sharks
Here's an idea. Poll your class to see which of these are most dangerous to people.
  1. Alligator Attacks
  2. Lightning Strikes
  3. Tornadoes
  4. Animal-Related Fatalities
  5. The Number of Injuries Associated with Home-Improvement Equipment
  6. The Number of Biting Injuries Occurring Annually in New York City
  7. Bicycle-Related Injuries and Fatalities
  8. Beach Injuries and Fatalities
  9. Dog Attack Fatalities
  10. Hunting Incident Fatalities

Students can take a survey during recess or after school. Graph the results in Excel, Max Count, The Graph Club, or any other program. Once all the data is graphed, show them the information from Florida Museum of Natural History, University of Florida.
There should be some surprises that your students will want to share with their parents. Let us know how it goes.