Space telescopes are some of the most precise and complicated machines ever built. Not only must they survive the harshness of space travel, but they also need to be incredibly accurate: misalignments by fractions of a millimetre can have huge effects on the quality of the images they capture. In 1990, the Hubble Space Telescope became the first…

The camera obscura (Latin for "darkened room") is the earliest optical device and goes back over 2500 years. The small pinhole or lens at the front of the room allows light to enter and this is then "projected" onto a screen inside the room. This differs from a camera, which projects its image onto light-sensitive material.…

The study of shadows is a common elementary science topic that facilitates students' development of understanding about light and associated waves. All elementary students have observed numerous shadows, but need assistance in developing understanding. Previous research studies about shadows were utilized in organizing aspects associated with…

The familiar kaleidoscope toy was developed by the Scottish physicist David Brewster (1781-1868) in 1816, patented by him in 1817, and described in his 1819 book, "A Treatise on the Kaleidoscope." Generations of elementary students have made their own kaleidoscopes by assembling three microscope slides inside a tube and looking through it at a…

We have developed two kinds of optical experiments: color mixture and fluorescence, using mini-torches with light emitting diodes (LEDs) that emit three primary colors. Since the tools used in the experiments are simple and inexpensive, students can easily retry and develop the experiments by themselves. As well as giving an introduction to basic…

Presents two views about lenses and optics in attempt to clarify a story written by Carolyn Hermann, "Through the Magnifying Glass." Cites two references for additional reading on students' optics difficulties. (RT)

Procedures for demonstrating rainbows in the classroom are provided. Materials required include a clear plastic box (the size of a shoebox), water, and an overhead projector. Also tells how to make a rainbow on the chalkboard using colored chalk. (JN)

Teachers may introduce students to anamorphic art (images designed to be looked at with conical mirrors or with mirrors diagonal to the image) with inexpensive cylindrical mirrors. By using polar graph paper, images can be made "correctly distorted" and will appear normal when viewed with a cylindrical mirror. (DH)

Discusses laser demonstration for invoking interest in science, especially physics. Describes some examples, such as diffraction, scattering, expansion by diverging lens, internal reflection in a light pipe, and illumination through optical cable. Provides some practical hints for the demonstration. (YP)

The ENKA Project is concerned with two major problem areas: the conceptions of physical and chemical phenomena, central to an upper level course, held by compulsory school pupils (grades 7-9) and the implications from descriptions of pupils' conceptions and ways of reasoning for current teaching practice. To determine conceptions held, pupils were…