Both Arnold and Wheaton have been serving educational establishments for many years, and it's good to see that they've remembered this fast on their entry to the micro software market. Not only do they encourage users to make a back-up copy of their programs, where necessary, they provide a menu program. (Unfortunately, there is a small error in this routine which I pointed out to Arnold Wheaton several months ago, without response. Line 40 requires TAB(15,5) between the first "MENU"; and CHR$(141)) to facilitate the running of multi-part programs on discs. Competitors who charge 50% of cost to exchange and those who ignore all requests for help, please note! Hopefully, colleagues will ensure that Arnold's continue to trust us!

All the programs are excellently documented and well packaged in plastic 'book' format. I wonder how much this packaging adds to the cost of the program and whether schools would prefer a cardboard box and discount? Most schools will, I suspect, standardise their cassette filing system on the cassette box for convenience and there'll be a lot of plastic books surplus to requirements!

Most of the user guides recommend that the programs are used with groups of children rather than individuals and that the learned should have had experience of the topic before attempting it on the computer. Whatever the concept being taught, it's important to remember that concrete experiences must come before use of the computer and that the interaction between children using the program is usually more important than that between the individual and the computer.

The concept of angles is introduced by showing that they are a measurement of turn and in each of the three modes in which Angle Turner works, the user can opt to work in 90 degree, 45 degree, 10 degree and single-degree intervals and the parameters can be set by the teacher. It is, therefore, a program that can be used profitably by children of a wide range of age and ability.

If the program is run on a cassette system, each mode is a separate program and loaded individually; if used with a disc system, the user is taken straight to a menu from which the option required can be selected. 1. Demonstration Mode: This allows the teacher to specify an angle, which is constructed on the screen, with or without the caption which shows the value of the angle being drawn. 2. Practice Mode: a) The computer displays a randomly selected angle (within the option selected) and invites the user to estimate the angle. b) A randomly computed angle is displayed on the screen in digital form. The user is invited to stop the computer drawing the sector when it has reached the size specified by the digital reading. The teacher can: i) set the acceptable margin or error; ii) specify number of goes before changing from mode a) to b); iii) specify number of incorrect tries before computer provides assistance. 3. Tutorial Mode: This is intended as a revision program with little need for teacher assistance.

The computer draws a sector and the user is invited to clear the screen when the computer will start to redraw the sector. The user has to stop the drawing when the sector is the same as the original. After each attempt they are given the option of trying to refine their answer.

This is a good example of a structured environment type program offering flexibility, which means that it would make a useful addition to any school's collection of mathematics programs. Two small criticisms: the explanation of the user of the T key (for teachers!) I found a little wooly and the value selection page might have been simpler.