O Level Revision

Algebra and Trigonometry are two cassettes from Cheshire Cat containing maths programs covering O Level revision.

Algebra is in three parts and covers expansions, factorisation, equations, change of subject of formula, variation, indices, surds and fractions.

Each section is split into a number of topics. For instance on choosing equations, the user is given the choice of tuition and questions covering linear, quadratics and fractional equations.

In fact a very wide range of topics is covered in each section.

The progam is menu-driven and one can step backwards or forwards through it - a useful facility when using the tuition sections.

The program first demonstrates how to solve a number of problems covering the chosen topic, then displays a self test to be worked out on paper. This is followed by the answers and if the user finds difficulty understanding how a solution was obtained the working can be displayed.

In the tuition mode, emphasis is given to important teaching points by displaying each new stage of the calculation in a Hashing mode.

Trigonometry is designed in a similar way to that of Algebra except that graphics are used to good effect in the tuition mode to give excellent examples of how various trigonometrical rules can be applied to real problems.

Topics covered by Trigonometry are basic trigonometry, angles of elevation and depression, solution of triangles, bearings, sine and cosine rules.

All the programs give excellent tuition and screen displays are well set out but rather monotonous. No use is made of contrasting background colours to emphasise teaching points and apart from using different background colours for tuition, question and answer modes, very little attempt is made to use the excellent colour facilities available on the BBC Micro.

As far as 1 could ascertain, answers were accurate and layout of calculations was shown in clear and easily understood stages. The programs contain very useful revision material and would be a boon to any student requiring self programming revision exercises or visual reminders of how particular problems are tackled.

However, my one big reservation is that there is no provision for any alteration of data within the programs and because of this they may be of limited use in schools. Having said this, the complexity of the programs in respect of the tuition modes make changing data extremely difficult to allow for.

John Daddy