The material they are talking about leads children through all sorts of learning tasks using spoken cues. It is engaging stuff, often culled from the huge shopping basket of titles aimed at the home. But what is good, where can you get advice, and how do you choose?

It’s too easy to eschew titles that seem playful, such as Sierra Adiboo, which aims to help with counting and reading. This title has four and five-year-olds counting vegetables, sequencing events and matching colours, letters and words. The 30 activities - all rich in cartoons, songs and speech - are on three levels of difficulty. As a starter for matching letters, children have to move a robot’s limbs to match those of another. If that’s accomplished, and the children don’t hike themselves up a level to get more things to match, the machine offers to do it for them.

As the children play, the computer monitors them, bringing in new activities and giving a progress record for each child. This is rare cleverness in software.

In Elmo’s Pre-school, the squeaky Sesame Street character provides masses of encouragement for children doing simple number and letter activities.

Madeline’s European Adventure is more convoluted: to solve a puzzle and start exploring Europe, they must sell flowers to buy a ticket, get a photo to collect a passport to go exploring, and so on. While the aims are different, both offer exceptional help, with few sticking points like textual menus. This is also rare.

It’s the computer storybooks that quickly find favour in school. The new UK English version of Arthur’s Birthday reads the tale to the child, with the words highlighted on screen. Alternatively, they can read the story themselves, and click on the tricky words as they go.

What this and the other programs have in common is that young children stick with them and make progress independently. However, we’re usually left to find where they match the national curriculum for ourselves, with only a software catalogue to help.

“Romrats”, a new mail-order club aimed at parents and children, is an intriguing step forward because it at least offers some hands-on shopping. Club membership includes three CD-Roms a year, each listing more than 100 titles classified by age, machine and learning objectives. Better still, it includes demonstration versions of 50 titles.

But you have to cross check: it is worth consulting the selection of the Parent Information Network (The TES, February 14, 1997) or taking local advice. Over the past few years the National Council for Educational Technology has spun hundreds of CD-Roms to assess whether they tie up with the school curriculum. They publish the results on paper and on the Internet.

David Hassell, NCET’s programme manager, offers some pointers to help schools decide what is useful. They are based on a scoresheet used by NCET,though he says it need not be followed slavishly. “Most titles have weaknesses, so the key question is: could you use this to improve teaching and learning?”