what intresting facts have you told to your students?

Question: what intresting facts have you told to your students?
- Keywords:
  facts,
  interesting,
  student,
  told
Asked by pricej to Helen on 13 Jun 2011.
- Helen Fletcher answered on 13 Jun 2011:
  
  Hi pricej. Only 10% of the cells in your body are human. The other 90% of cells in your body are bacterial (mainly in your gut). These bacterial cells help us digest our food, keep our skin healthy and help fight off disease causing bacteria.
  
  The earliest form of vaccination was called “variolation”. People would pick a small pox scab off one person then use a long pipe to blow it up the nose of another person (eewwww). This would protect people from smallpox but it was pretty dangerous and 1-25% of people would die following variolation!!

Question: what intresting facts have you told to your students?