A square lattice is used to generate classroom activities, such as counting the number of squares in a lattice of a given size. (MP)

Four answers to a probability problem involving a perceived coincidence are discussed. (MNS)

The relation between the area of a rectangle and its perimeter is clarified by looking at patterns. Several examples involving rectangles with integral sides are presented. (MNS)

A familiar procedure for generating magic squares is reviewed. A surprising pattern is noted. (MNS)

Described are results obtained by students investigating double-diagrams, including discoveries of properties and accompanying proofs. (MP)

Relationships between the linear dimensions, surface area, and volume of parallelepipeds are examined. (SD)

An activity that offers computational practice, pattern recognition, and the formulation of generalizations is described. (JT)

Tree diagrams with numbers in a given pattern generate questions related to pattern recognition and number concepts such as binary numbers and exponentials. (MP)

Three games played with regular bridge decks of cards are described. By playing the games students gain practice in use of basic operations on integers and in the development of strategies. (SD)

A problem concerning the generation of an array of numbers is posed. The author examines the use of this problem in several secondary-school and college classes. (SD)

This activity is designed to help students recognize and extend rectangular patterns and to use patterning to formulate rules for "nth" cases. Three worksheets are included. (MNS)

Curiosities offer an interesting alternative to traditional methods of attacking problems. An illustrative situation is given, with graphical, computer, and analytical methods used to solve the problem. (MNS)

Activities involving estimation of the number of objects in a configuration can motivate students to consider parametric models. (SD)

Introduces students to nonperiodic tiling and allows them to construct their own sets of kites and darts through a series of explorations, conjectures, and discoveries. (ASK)

Argues that mathematics is, to a large extent, the study of patterns. Presents an activity in which students search for patterns in the Fibonacci sequence and Pascal's Triangle. (ASK)