The scene is a particularly worthy lesson on the merits of spreadsheets in biology; attention spans are fading and the noise level is increasing. How do you bring them back? “Now, let’s try and represent this growth curve with some pictures.” Snap - the graphics packages are out already and dismembered body parts are spread liberally across the growth curves. I always feel guilty about this “waste” of curriculum time. However, understanding how images can be manipulated and used is just as important as editing text in this digital age.

A good piece of software should educate the learner in the principles behind the application as well as its execution, and Adobe Photoshop fits the bill admirably. It has a deceptively simple palette of tools, so it can be used by young children, but hiding below the surface are levels of complexity that will satisfy the most demanding of graphic designers.

Files of almost any format can be imported and exported by Photoshop: Gif for the Internet; TIFF and EPSF for desktop publishing; Kodak Photo CD for your snaps. You can also buy add-on programs, known as “plug-ins”, which provide an exhaustive range of special effects and filters which can be applied to pictures.

Although expensive, Photoshop is a versatile graphics tool which can handle most graphic tasks and will also provide hours of fun. Some schools will be able to justify its price tag by exploiting its ability to create professional-quality publications that would incur high costs with outside publishers.

You don’t have to display any skills with a pencil or paint box to take advantage of software like Adobe Photoshop. There are many ways of obtaining pictures: from CD-Roms found on magazine covers or, if you have an Internet connection, there are massive libraries available. However, the best pictures are the ones you take yourself. Pictures can be taken with a conventional camera and the film processed on to a Photo CD; with a CD-Rom drive these pictures can be imported directly into Photoshop. The new Macintosh Performas with built-in TV and video ports can painlessly capture pictures taken from television, or with a video camera or video-still cameras, such as the Canon Ion, or with the digital Apple QuickTake 100 camera.

Think of Photoshop as a digital darkroom that can manipulate pictures without messy chemicals. Many of the tools actually refer to darkroom techniques such as burn and dodge. Removing the flagpole behind the headteacher’s portrait, eliminating scratches or sharpening an image can all be accomplished with little effort. Photo-retouching of monochrome pictures in-house can cut costs when producing school magazines, posters and other publications.The cost in time must be weighed against the satisfaction of doing it yourself and giving children the opportunity to understand the processes involved.

Once the basic skills are mastered, more creative uses begin to develop. Artists tend to shy away from new technologies and extol the virtues of traditional methods. Comments such as “computer images always look the same” abound. Scanning a sketch or piece of artwork into Photoshop allows rapid exploration of colour schemes, solarisation, distortion and collage; often surprising things happen which generate more ideas. Soon a subculture of Photoshop aficionados can be found swapping techniques and recipes. Many of these effects are stimulated by television, and lengthy discussions ensue on methods and real-world applications of image manipulation. The CD-Rom which comes with Photoshop has a superb gallery of movies with graphic artists demonstrating skills. This is one of those programs where children demand to see the manuals in the hope of gaining more pups (Photoshop User Points).

On the down side, the results displayed on the screen often aren’t matched by the print-out, especially when using an inexpensive colour inkjet. Making friends with someone who has a quality colour printer, such as a local typesetting bureau, feeds the creative process.

Children enjoy the more bizarre features of Photoshop, manipulating pictures of faces by applying swirls, twists and distortions and producing flip-books of each stage produces endless entertainment. Pictures can be converted into a movie using an animation program, and there is a little utility called “pict to movie” for QuickTime on the Macintosh which will convert a sequence of numbered pictures into a movie. Adding a soundtrack and titles (using the text tool in Photoshop) can produce impressive results. Adding movement to pictures in this way leads inevitably to multimedia productions, so be prepared to buy a large hard disc for storage. There are ways of capturing still images and animations on videotape.

Photoshop can be used for painting from scratch, in which case it is a good idea to invest in a pressure-sensitive graphics tab-let - the Wacom Art Pad is excellent value. Sceptical artists soon change their point of view when they have a responsive and versatile pen. However, packages such as Dabbler and Painter, often bundled with the Art Pad, are probably more appropriate for this.

Other image manipulation programs offer similar features but Photoshop is a recognised standard and has a well thought-out interface which unveils its talents as you dig deeper. Many excellent books extend and ex-plore aspects of this program; some have CDs packed with utilities and full versions of software such as Kai’s Power Tools. Photoshop also has a major presence on the Internet, with World Wide Web pages devoted to tips, recipes for special effects and free filters.