Reading maps is much like looking at coordinate grids. The latitude and longitude lines resemble the x and y axises so much, that it is easy to make the comparison. So when studying about the early European Explorers, it seemed natural to combine math with a geography lesson.
Now, I would LOVE to say that I thought of this idea on my own....but I didn't. It was a worksheet in my ELD book...I just adapted it to fit my needs..and add a bit more rigor.
I gave my students a blank map of the world (that I found here). They then were given a set of blank coordinates. We reviewed how to find latitude and longitude spots on the globe (keeping in mind that the longitude lines CURVE) and the kids were off. The kids needed to find the first coordinate and then connect it to the second set of coordinates. In some cases, there was a third stop on the voyage.
Kids learned very quickly that some voyages took them around South America or Africa, as if you drew a straight line you would have to sail your boat across land...a feat they knew was impossible.
After all of the routes were set, the students were then given an information sheet with data and facts from the various explorer's journeys. Using this information, they decided which set of coordinates belonged to which sailor. It was really neat to hear them reasoning things out and deciding upon which person did which route.
For the final piece, I had the students write a little summary paragraph of the voyage, taking all the data they had and putting it into their own words.
And there you have it....a social studies/math connection :)