Have students test the shrink coefficient of different fabrics by assembling a variety of fabric squares of equal dimensions. Assign several students teams to take them home and wash them in either hot or cold water, and compare the results the next day. In arctic climates, however, probably the hardest working animal is the sled dog. While several different breeds of dogs including the Siberian Husky and Samoyed are used on sled teams, the most popular seems to be Alaskan Malamutes. Originally domesticated by the Malamute Eskimos for who they were named, these dogs are capable of pulling fully loaded sleds for literally hundreds of miles across the frozen tundra.
Malamutes are well adapted to the cold having two coats of hair.
The outer layer is quite coarse and long while the inner coat is extremely dense with an oily feel. Because of this layering, Malamutes never get wet to the skin, even if they fall through thin ice. Racing sled dog teams can have up to 16 members who tend to be lighter than those that carry freight. Unlike oxen or horses, sled dogs are controlled by verbal commands instead of pulling on reins. The most important member of a dog team is the lead dog, which has total control of the other members.