Katharine E. Dopp was well-known as a teacher and writer of children’s textbooks at the turn of the 20th Century. She was among the first educators to encourage the incorporation of physical and practical activity into the elementary school curriculum at a time when such activities were becoming less commonplace in a child’s home environment. The Tree-Dwellers – The Age of Fear is the first in a series of elementary school texts written by Ms. Dopp that focus on the anthropological development of early human groups...