An activity that shows how mathematics can be used to model events in the real world is described. A way to calculate the area of the sun covered by the moon during a partial eclipse is presented. A computer program that will determine the coverage percentage is also included. (KR)

Explores the production of shadows for drawings using the LOGO computer language and Affine Geometry. Explains the methodology of the shadowing and lists the Affine Turtle procedures. Provides for different versions of LOGO. (MVL)

Describes how three dimensional LOGO was used in a workshop session for secondary pupils and mathematics teachers. Provides many commands and output drawings. (YP)

Discusses dimensionality in Euclidean geometry. Presents methods to produce fractals using LOGO. Uses the idea of self-similarity. Included are program listings and suggested extension activities. (MVL)

Considers activities that use LOGO to slide, turn, and flip the "turtle." Uses non-LOGO tools such as cutouts, pattern blocks, and tangrams to enhance the motion work. Provides examples and programs with explanations. (MVL)

Provides a software program for determining PI to the 15th place after the decimal. Explores the history of determining the value of PI from Archimedes to present computer methods. Investigates Wallis's, Liebniz's, and Buffon's methods. Written for Tandy GW-BASIC (IBM compatible) with 384K. Suggestions for Apple II's are given. (MVL)