Although computers give access to a world full of information via CDs and the Internet, the sad fact is that this world usually has to be viewed through a 13in window - the standard computer monitor. That’s fine if you are home and alone, but not so clever when you are a teacher with a class of 30 inquisitive children. The good news is that there are some new, affordable ways of sharing one computer image with a whole class.

Teachers won’t spend time building and gathering digital resources unless they can use them in class. Many find a brilliant CD or website and then they have to send children away for a solitary first encounter. Sometimes a small group is best, but often the ideal introduction to a new resource is to have the teacher take you through it first.

You may also want to produce your own computer presentations using text, graphics and sound. The advantage here is that once the information exists electronically, it can be revisited by students who were away or mentally absent when the work was first covered.

There is now plenty of software for creating presentations. If the school has the Microsoft Office suite, PowerPoint (PC and Apple Mac) is a useful starting point. There are plenty of ready-to-use templates and the Presentation Wizard helps you select the most appropriate. Then all you do is fill in the content. Some teachers are using PowerPoint to print notes for students at the end of the lesson.

HyperStudio (PC, Mac and Acorn) is more free-form but works well on all computer platforms. Again, templates and backgrounds are provided and individual applications can be linked together so that a series of key lesson points could be accessible later in the library.

Schools are using web pages as resources. Web-authoring software, such as Front Page (PC)and Adobe PageMill 3 (PC and Mac), makes it easy to link pages of text and graphics. These can be copied on to a school’s intranet (internal network of web-pages) so that they have a life beyond the lesson. There will also be times when students need to make a presentation. Pupil motivation is increased and learning is shared.

So once created, how do you share these presentations? The simple way is to buy a bigger monitor. Several schools have them fixed high on the wall, allowing whole classes to see what’s on screen. Primary schools find that even a 17in monitor will allow a teacher to share a talking story with a whole class at an extra cost of just pound;100 more than standard - just the tool for literacy hour.

The next option is to link the computer to a large television, using an adaptor box to convert the computer signal to a video format. These are known as scan convertors. The 3D Rage card is a standard video card for a computer monitor, but it can also run any large television simultaneously (the television needs a SCART socket or separate video-insocket).

Video projectors show computer images on a screen up to 150in wide, so the whole school could watch. There are two types - video-only and video and data. Sharp has become a leader in video projectors - its XVZ1E can effectively turn the assembly hall into a cinema.

Data projectors take video and computer output and provide a far greater resolution. Prices are falling: the compact CTX ExPro now costs around pound;1,300 excluding VAT from Liesegang and other suppliers. The CTX projector works well for images up to 150in wide - even in daylight with zero blackout. Better still, the projector is the first to use cheap quartz halogen bulbs costing pound;16 rather than the usual metal halide bulbs at more than pound;200 each.

Sharp’s new data projector, the XGNV2E, which retails at around pound;4,000, is also a fine workhorse. It is small enough to transport but robust enough for school life, and works with both Mac and PC. Just launched by Phillips is the new Hopper projector - the brightest and quietest projector I have seen so far - at around pound;3,400. Three years ago, such performance would have cost pound;12,000. Just Projectors will display a range of computer projectors at Bett.

A new technology known as digital micromirror device (DMD) is about to revolutionise projector clarity and brightness. It uses a system of mirrors to reflect light and is, therefore, brighter than the LCD panel used inside today’s models through which light passes. The technical achievement is also striking: each DMD chip is only the size of a five pence piece but contains more than 480,000 mirrors. If a grain of salt were to land on the chip, it would cover 900mirrors.

In Focus has just launched a new projector using a second-generation DMD device. The LP 425 costs just less than pound;4,000 but represents a bright new future for projection from computer and video. It’s also small and light enough to fit in a large handbag. Just the thing to light up the walls on a parents’ evening.