See and hear : the journal on audio-visual learning (1945)

portunity for student group activity. Each student can assume responsibility tor various parts of the diorama. It is also an activity in which all ability levels can participate. Information gathering, construction, modeling, lighting: all offer problems that students can work out. A diorama can illustrate many learning situations, such as geologic periods, plant and animal habitat groups, good health practices, and others. Working models are a valuable addition to instruction. They help illustrate and make clear the principles or applications being studied. To feel and see in the third dimension gives pupils added help in understanding and seeing how things work. In science classes not only experiments and demonstrations, but also the actual room environment, is of value in motivating instruction. Here again visual material is the keynote for developing good room environment. Pictures, or displays of material, can be used to arouse pupil interest and tell what is coming next. Exhibits attractively arranged with suitable and colorful background, displays of material pertaining to topics being studied, and experiments being carried on will all help to make the science room a place where pupils like to work. Of course, this material should be changed often for it is essential to keep it up-to-date. One of the most important problems in visualizing science instruction is in the selection and use of the material. In selecting materials, several things should be considered: accuracy, adaptability to grade level, and suitability to the purpose of the lesson. Audio-visual materials, particularly films, have sometimes been misused, leachers need to develop skill in using audiovisual materials, as they develop skill in the use of any other teaching technique. The use of these materials should be planned as an integral part of the lesson, not as something added or as entertainment. Audio-visual materials have many uses. They can be used as a means of arousing interest, introducing a topic, giving accurate information, reviewing material, or even as an evaluation of a lesson. Fortunate is the pupil whose teachei knows and uses audio-visual materials to make science instruction a vital, up-to-date, meaningful part of his education. • SEEING STARS on 2"x2" Slides by Harold Hoinfeld Roosevelt School, Union City, New Jersey PRESENTING A UNIT IN ASTRONOMY is often difficult on the upper elementary or junior high school level, for evening field trips are usually impractical, and viewing the stars is often difficult in large cities because of natural haze or smoke from factories and railroads. However, one solution of the problem is for the teacher and his pupils to prepare a classroom series of 2" x 2" slides of various constellations. All the equipment needed is a 35 mm camera, a tripod, one or two floodlights and a piece of etched glass. Drawings of the various star formations are made with black India ink on while oak tag or drawing paper. Generally the camera can be focused from 2i/2 or 3 feet to infinity. Drawings can be made on 81/2" X 11" paper if the camera can be focused at 2i/2 feet, or 11" x 14" paper at 3 feet. No special lens or close-up attachment is necessary. The procedure for taking pictures of the star constellation drawings is as follows: 1. The camera is mounted on the tripod and placed at the shortest distance where it will be in focus. 2. Fix the camera for time exposure and press the shutter button. This will open the lens. Then turn on the floodlights. 3. Open the rear of the camera and hold a piece of etched glass there. This will enable you to see the area to be photographed. 4. Place a drawing in this area on the wall or box. It will appear upside down when viewed through the etched glass, but don't worry about this. 5. Lock the tripod in place. Make sure it does not move. 6. Trip the shutter to close the lens. Load the film into the camera. All that is then necessary is to photograph your series of constellation drawings. It may be advisable to take a series of shots at different exposures and at different shutter speeds. Our experience has been that using Super XX film with an exposure of f.8 at 1/100 second or f.ll at 1/50 second gives the best results. When the film is developed, the white area on the drawing will be black, like the night sky. The black India Ink drawings of the constellations will be white, similar to the star formations that are being studied. When these are bound into slide form and projected, a most realistic impression is gained. Pupils will enjoy making drawings of the constellations and mounting and binding them as 2" x 2" slides. They will take added interest in seeing stars as their drawings appear on the screen as an interesting addition to the visual education program. • "SCIENCE VISUALIZED" 27