The essential reference tool in geography is the atlas, as basic as the dictionary in English. But atlases need to be updated more frequently than most other reference books, and the latest editions have to compete with a new generation of electronic atlases.

The latter have the advantage that the atlas becomes more interactive - you can zoom in and out, it is easier to compare maps, and you can even customise maps to meet your needs. But, in reality, with access to computers still limited in many schools, the old-fashioned book version is the atlas of choice in most classrooms, most of the time.

Traditional atlases do have their advantages. As a form of reference, they are easy to pick up and find your way around (assuming, of course, that pupils have been taught the basic atlas skills). In this context, particularly in secondary school classrooms, an atlas is an important resource for pupils doing independent geographical enquiries. Clarity is another advantage. The print quality of most atlases these days is superb and better than can be achieved by printing from a CD-Rom.

Then there is the cost. According to one study, the average replacement value of atlases per pupil is between 98p and pound;1.58 - not bad, considering some schools only replace their atlases every 10 years or so.

So, apart from cost, what else should you look for when choosing an atlas? Perhaps the most important factor to consider is the level at which the atlas is aimed. This is usually well signalled in the title, but it is always worth checking inside. Many schools choose an atlas in the same way you would buy your child a pair of school trousers - hoping they will grow into them. This can be a problem for pupils lower in the school or for those with learning difficulties, who would do better with an atlas targeted at their level. Assess the balance between topographic and thematic maps as well as the proportion of maps devoted to the British Isles, Europe and the rest of the world. Beware of atlases that are issue-based. The issues may change, as might the exam specification.

Check how easy the maps are to interpret. Too much information will make them more difficult to read - though, paradoxically, maps with little information can be too abstract for pupils to understand. Make sure you buy one that incorporates recent political changes and the latest census figures.

Collins Foundation World Atlas Collins pound;7.50

Here is an atlas that really targets its intended audience. Collins Foundation World Atlas is specifically aimed at KS3 students and is pitched at just the right level. The publishers have decided to sacrifice breadth for depth, focusing on the countries most frequently studied at KS3 - Italy, Japan, Kenya, Brazil and Australia. There are regional maps for each country, together with thematic maps and satellite images. The maps are helpfully large, many covering a full spread. Most of them are clear and uncluttered, making them easier to interpret. By going for depth, some areas are not particularly well covered, but this is probably a price worth paying if you want an atlas tailored to the curriculum and your pupils.

Longman Student Atlas By Olly PhillipsonPearson Longman Geographical Association pound;11.99

There is a wealth of detail in this atlas that clearly marks it out as being aimed at GCSE level and beyond. However, it left me wondering: at what point does an atlas become a textbook?

The design has benefited (or suffered, depending on your viewpoint) from the Dorling Kindersley treatment. There is a lot of text, with small photographs and diagrams around the page. Some spreads are so crowded that the maps themselves seem to fade into the background. However, students could spend hours poring over this atlas and it could be a valuable source of reference material on a range of current issues - for example the Mediterranean and tourism, Africa and fair trade, the USA and genetically-modified crops. It’s an atlas, but not as you know it.

Oxford Primary Atlas Editorial advisor Patrick Wiegand Oxford University Press pound;6.99

This is a lively, colourful atlas aimed at the younger market. However, I would have no problem using it with Years 7 to 9 pupils - and its child-friendly design would be positively beneficial with less able pupils in secondary school.

The introductory spreads on atlas literacy and numeracy explain the features and how to use them. Each map has a very clear locator and key, and is surrounded by an alphanumeric grid as well as the standard lines of latitude and longitude. Everything about this atlas is visual, from the contents page to the illustrated key and the explanatory diagrams. I wasn’t so sure about the photos. Although they add yet more colour, they take space that could have allowed the maps to be even larger.

Oxford Student Atlas Editorial advisor Patrick Wiegand Oxford University Press pound;9.99

Oxford Student Atlas is billed as “the perfect atlas for all 11-18 year-olds”. Unless pupils arrive at key stage 3 thoroughly familiar with using an atlas from primary school, this would not be the one I would choose to start with. Having said that, it does all that you would expect of an atlas for students at KS4 and beyond, using clear, well-designed maps.

Like its stable-mate, Oxford Primary Atlas, each regional map is accompanied by a locator, a key and an alpha-numeric grid. There are also thematic maps for each continent, dealing with climate, ecosystems, population and economic geography. Visually, the atlas is enhanced by satellite images, mainly to illustrate environmental issues. Another useful feature is the datasets for each country at the end of the atlas.

Philip’s Children’s Atlas By David and Jill Wright Philip’sRoyal Geographical Society pound;9.99

This atlas-cum-reference book for children was first published in 1987 and is now in its 11th edition, but has lost none of its original appeal.

Opening with an introduction to Planet Earth, it takes readers on a journey around the countries and regions of the world. All parts of Europe are given equal coverage, so this atlas might not be the best for an in-depth study of the UK.

The maps are simple and well designed for primary pupils and each map is on a double-page spread with the explanatory text. The emphasis throughout is on creating a sense of place, with colour photos and links to issues, events and people. Further variety is added with fact boxes, flags, stamps, and quiz questions. There is one spread about atlas skills, which are not fully developed. In this atlas, places take priority over the maps.

John Widdowson is a geography textbook writer