The audio-visual handbook (1942)

II Types of Visual Aids and Their Uses Classroom Experiments and Blackboard Demonstrations THESE aids in instruction are familiar to nearly all teachers. The classroom experiment, conducted by the students or by the teacher, offers many opportunities for satisfying the creative urges and instincts of the pupils. The pupils should be relied upon as much as possible for this type of classroom procedure. Science and agriculture texts include instructions for the germination of seeds, growing of inseets, preparing an aquarium or a terrarium. Biology, physics, and chemistry texts outline an abundance of experiments which may be conducted by the students. Some of these experiments are too tedious for instructional economy and should be eliminated. Other experiments are pertinent and effective. One teacher in a junior high school develops much interest in silk, its production and importance, An Aquarium Tadpole through the culture of the silkworm in the classroom. Eggs are secured, an appropriate case is placed in the corner of the room, and the pupils in that room are able to watch, from day to day, the gradual change from one life form to another. A few skeins of silk and silk samples serve to complete the story in a manner many times as effective as the most interesting story in a text. There are a few simple rules which should be observed in connection with the use of all visual aids to instruction, particularly classroom experiments and blackboard demonstrations. They should be directly related to or a part of the information and instruction to be imparted to the pupils at the time. They should be accurate and purposeful, well planned in advance, and executed with care. Most of all, any demonstration material in the classroom should be clearly visible to all in that room. Frequently, effective instructional procedure has been wasted because some members of the class could not see the experiment or demonstration clearly. 25 w f^.: -fev W *P%^'^ lpT^Bpr^