This professional, well-tested program comes from a company that has become a byword for quality educational software. In terms of presentation and clarity of instruction there are few competitors.

In each of the three options one is able to select a difficulty level and, in the case of Estimation, an accuracy level. Although it is menu-driven, there is a summary of special keys which affect the operation of the program, all of which are clearly indicated in the handbook and program.

As is so often the case with this sort of software, one is often in difficulties deciding whether it should be for class demonstration use or for individual experimentation. Obviously it lends itself to both, but in a classroom one needs a very big screen for single-height teletext characters.

In terms of the actual operation of the program, the student is expected to be able to develop his ability to estimate based on increasing success with the tests given to him. A clear indication of his level of accuracy is shown by a bar chart on the right of the screen.

Approximation may be performed to a top level of five decimal places and five significant figures. In Standard Form, the student may be asked to convert floating point to standard form or vice-versa.

A straightforward, practical and useful tool for the mathematics classroom.