The ZX81 BASIC Book, published by Newnes Microcomputer Books, is more staid in approach than the others reviewed in this section of ZX Computing, and for that reason is sure to appeal to schools. Although the approach is fairly straight, the book is far from dull, with witty(?) chapter titles like "Gone out, bizzy, back soon" to introduce subroutines, and "Graphics ride again!"

The book methodically covers the ins and outs of the ZX81 starting with general information on what computers can do, followed by a short introduction to computer languages and binary arithmetic, and then a brief section on what a program is - using a sample 'program' describing certain actions by Mickey Mouse in a Walt Disney cartoon. Once you've traversed this ground, and worked out how to plug your computer into the telly, the book gets down to work. Direct input commands are covered, and - in a section sure to confuse newcomers who don't have a maths backround, or don't want to get involved in such things at such an early stage - then the priority of mathematical operators (such as multiplication before addition) is discussed. Already I can sense newcomers flipping past this section in exasperation, looking for something a little more directly relevant to their needs.

We are already up to chapter eight (some of the chapters are only one or two pages long) before the first particularly useful information for first-time bewildered users is presented. The use of LET to assign values to variables is explained, followed (in subsequent chapters) by such things as the use of commas in PRINT formatting, the use of the EDIT function, trigonometrical functions (you can see this is just the sort of book your teachers would leap on), and GOTO and FOR/NEXT loops.

The book would be, I believe, fairly heavy going, despite its simplicity, for a person who has just picked up a computer for the first time, but when used as a text to guide pupils who have the benefits of a live teacher on the spot, would be very useful indeed. It is difficult to imagine why the material has been presented in this order, with GOTO assigned a lower priority than converting radians to degrees, and loading and saving programs is considered less important than finding natural logarithms of square roots.

If you are teaching a class of 14-year olds the rudiments of computing using a ZX81, and you want to do it 'by the book' this is the book to buy, but if you're not... have a good look at it in the shop before you decide. ZX81 BASIC Book, Newnes Technical Books, ISBN 0408011785.