This lesson will start with compiling knowledge from the students about what they know about maps and Google Earth maps. Once you write some responses on the board, start with the Powerpoint presentation, which will prompt more questions.
Think of some clever ways to remember longitude and latitude (eg. 'long'itude is loooong, up and down; 'lat'itude, I'm late, so I have to run across the world).
Then comes a coordinates exercise, which you can complete with the students on the board.
Next comes the Google Earth section - instruct the students to get a tablet (pairs, groups, or individual depending on the resources. Download Google Earth before lesson if necessary. Open up Google Earth on the white board screen so the students can follow along, and teach some of the functions with a famous place - I used Niagara Falls to teach 'search', 'places', and different functions under 'layers'.
After that I provided their school's coordinates and instructed them to input them. Then they looked up their houses.
After playing around for 5 minutes or so, I asked them to put the tablets face down, and provided a short quiz. Once they answered the questions with words or drawings, they could start with the Google Earth Scavenger Hunt. I provided different coordinates and they had to input them and then write or draw their results.
*Note: some of the coordinates ended up inadvertently in the middle of an ocean - check your coordinates at home before you give them to the students!