Google Maps, once more, with feeling.

My idea for a math lesson that utilizes Google Maps would revolve around rates, and particularly one of the most talked about rates right now, miles per gallon.  After learning about rates, students would plan a long distance road trip.  They would be given a gas mileage rate and gas tank capacity, possibly by random draw (we could all chuckle about the student who got the 20 year old pickup with 10 mpg) or possibly allow the students to pick their own vehicles and look up gas mileage statistics.  Students would then have to plot a course to their destination, using the draw a line along roads tool to track distances so that they can decide where they would have to stop for gas.  For more advanced classes, you could include having to account for speed and time, planning where to stop for meals or for the night if the trip is long enough.  Here's a map from a trip I recently made to a reunion (we went to our inlaws' house and rode from them there, that's why it's so indirect, and I'm pretending we went straight back home to make a different route back), with stops added for theoretical gas stops. Here's the map.