The exploration, discovery, and generation of attractive two-dimensional designs as an approach to informal geometry and spatial learning is discussed. Six activities with brief instructions are presented. (CW)

Gives an example of an open exploration using trigonometric relationships in which the law of cosines can be deduced from the law of sines. Discusses the characteristics and value of the exploration process. (MDH)

Uses conic sections, trigonometric functions, and polar coordinates to solve the problem of determining the shape of a baseball outfield fence, given the distances along the foul lines and to straightaway center field. Graphing programs and calculators are utilized to plot different solutions. (MDH)

Described are some classroom experiences teaching the concept of symmetry by having students create frieze patterns using the computer software "mosaic." Examples produced by 14-year-old students are presented, and student thinking in developing the friezes is discussed. (MDH)