By handling numbers in unexpected ways, computers and calculators create headaches for computer programers and set traps for unsuspecting users by sometimes producing wrong answers. Specific examples of such computer/calculator errors are discussed. (Author/JN)

An algorithm for the calculator is given for determining the day of the week for any date. An instructional sheet, a worksheet, and a BASIC program are included. (MP)

A method of finding large primes is described. High school students can use the test using hand calculators, or by programing a computer. (SD)

The uses of programable calculators in the mathematics classroom are presented. A discussion of the "microelectronics revolution" that has brought programable calculators into our society is also included. Pointed out is that the logical or mental processes used to program the programable calculator are identical to those used to program…