It is common practice that children play outside in Norway in winter and babies are even encouraged to sleep outside while monitored by their parents. The general rule is that play or outdoor sleeps in prams are appropriate until the temperature is below -10 Celsius or 14 degrees Fahrenheit. Play and sleep outside must include appropriate wool clothing in addition to wool sleep sacks, etc. In the coldest winter weather, it is recommended that children wear a layer of thin wool closest to their skin followed by a thicker layer of fleece or wool and then a snowsuit. It is important to have extra clothes, mittens/gloves and hats to be kept at school. Rain coats, trousers and boots should also be kept at school.