The Tree Puzzle as a Teaching Device

Several years ago while teaching in the high school at Grinnell, Iowa, I found the Grinnell Flora and Our Trees by Prof. Conard very useful devices for teaching and particularly for motivating an interest in outdoor life. After moving to Davenport, with only a forty-five minute class period, and an impossible walking distance from desirable spring flora, one choice for the out-of-door study was the trees. Since students like field studies and the trees demand to make themselves known in the spring, I set to work to construct a guide to the common native and cultivated trees of our locality. It was my desire to use leaf characteristics wherever possible and build a guide adaptable to high school students of the tenth grade. The use of technical terms was avoided wherever possible. If the appreciation of nature is our objective in the teaching of elementary biology, and I believe it should be the main objective, why confuse the student with terms that will discourage him? The result of my effort is what· I have chosen to call the Tree Puzzle. The puzzle idea immediately attracts attention while the use of the term key means nothing to the student with little experience. The puzzle consists of a brief description as to how the game is to be used or played. A brief glossary of unavoidable terms was necessary along with a folding sheet of diagrams of leaves as to kinds, parts, shapes, margins, tips, edges, venation and the puzzling line of description comparable to the conventional key