After the PowerPoint, answer the following:
1) Describe what you think might have been the greatest invention of all time (not including the last two hundred years).
2) Describe an instance when you have invented anything or found a solution that has been useful to others.
We may want to check out the following links
http://www.smith.edu/hsc/museum/ancient_inventions/hsclist.htm
http://www.learnenglish.org.uk/words/Activities/ancientdr.html
.