An unusual way of using the long multiplication algorithm to solve problems is presented. It is conceptually harder, since it involves negative numbers but is easier to perform once mastered, since the size of the multiplication table required is smaller than the standard one. (MP)

One of the main purposes of a mathematics club is to provide the opportunity for students to study exciting topics in mathematics not ordinarily discussed in the classroom. Each of the 10 chapters in this booklet is a collection of related subtopics. Each idea is presented and discussed; bibliographies then suggest in-depth reading. The chapters…