The day dawned clear and warm on March 26, 1931, when Carl Miller started his rounds, picking up the 20 children who attended one of the two small schools in Towner, Colorado. Miller, a farmer by trade, had converted a 1929 farm truck to a school bus. The children ranged in age from seven to 14. By the time the buses reached the school, at 9 a.m., the weather had turned. The temperature fell from about 70 degrees Fahrenheit to below freezing, and snow had started to fall. The schoolhouse…