Highlighters are fun because you can draw and still see through it. Maps make a great different medium to draw on. The kids used these materials in a few different ways.
Some drew lines and shapes just like they would on any other paper.
Some filled in the spaces they found on the maps.
Some drew along the roads.
Some covered the entire piece with color. (But we could still see the map lines!)
It was interesting to see how the kids approached drawing on paper that already had something on it. Sometimes just a different paper or a different writing tool creates different thinking.