New! My book Some Adventures in Euclidean Geometry is now available for download on your iPhone, iPad, or iPod touch, and on your computer with iTunes for only $9.99 at iTunes: More info.
Click on links below for more information.
1. PAPER: A Sketchpad Investigation involving triangles & quadrilaterals 8 pp. @ USD 0.25. (A dynamic sketch on which the article is based is available at dynamic sketch )
2. Lulu BOOK: Some Adventures in Euclidean Geometry 219 pp. @ USD 4.00 to download - printed copy also available @ USD 19.99. (This book seeks to actively involve the reader in the heuristic processes of conjecturing, discovering, formulating, classifying, defining, refuting, proving, etc. within the context of Euclidean geometry. Extensive attention is also given to the classification of the quadrilaterals from the symmetry of a side-angle duality. Many examples lend themselves excellently for exploration on computer with dynamic geometry programs such as Sketchpad.)
3. Lulu BOOK: Boolean Algebra at School, Vol 1 147 pp. FREE to download as PDF - printed copy also available @ USD 15.00. (The main focus of this book is on actively engaging students in the mathematical processes of modeling and axiomatization. The book starts off with some challenging problems involving switching circuits. Students are then engaged in gradually developing a mathematical model in order to solve these problems. Eventually students are led through some proof activities to identify a suitable set of axioms.)
4. Lulu BOOK: Boolean Algebra at School, Vol 2 121 pp. FREE to download as PDF - printed copy also available @ USD 11.00. (The Teacher's Guide to Vol 1, provides a more detailed discussion and formal exposition of Boolean Algebra as well as a few more examples of Boolean Algebras, as well as a rationale for the approach used in Volume 1.)
5. Lulu BOOK: Elementary Logic 99 pp. FREE to download as PDF - printed copy also available @ USD 11.96. (This book provides a basic introduction to Elementary Logic suitable for high svhool and upwards, and is illustrated with examples from high school algebra, geometry, and trigonometry.)
6. New! Lulu BOOK: Making Democracy Fair: The mathematics of voting and apportionment 168 pp. @ USD 3.99 to download as PDF E-book - printed copy also available @ USD 15.00. (Using elementary mathematics, different types of voting procedures are examined and compared, as well as methods of apportionment used in some countries and/or other systems of proportional representation such as the United States Congress.)
SPECIAL LULU BOOKS OFFER, till 26 January 2017: Enter coupon code WINTERSHIP at checkout and save 15% on all print books plus free shipping. Sorry, but this offer is only valid in US Dollars and cannot be applied to previous orders. You can only use this code once per account, and unfortunately you can't use this coupon in combination with other coupon codes. This great offer expires on 26 January 2017 at 11:59 PM PST, so don't miss out!