We used a topographical map - the kind with a line around every 1000 feet of elevation. We enlarged a section of the map. Then we traced the line patterns, one at a time, onto cardboard and cut it out. We glued the cardboard pieces we'd cut out onto a cardboard base as we cut them out. We stacked up the layers of cardboard until it made the mountains and valleys shown on the original map. Then we covered the whole thing with paper mache (newspaper and flour-water) and painted it with green hills, white snowcapped peaks, and blue rivers and lakes. It was tons of fun for the kids, and they got a real feel for topographical maps.
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