Thought some here might be interested in this 1985 book of mine, "Boolean Algebra at School", which has been republished through Lulu Publishers and is available in printed form or as downloadable pdf. Though it's written for high school students, the approach might be of interest to those teaching post-calculus courses at college & elsewhere.
Boolean Algebra at School, Vol 1 http://www.lulu.com/product/paperback/boolean-algebra-at-school-vol-1/14244188 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. After development of the model and solution of the original problems, a section on systematization follows where students are led through some proof activities to identify a suitable set of axioms.
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