This dissertation work which is in the form of a book is an investigation carried out by the author attempted in order to explore the concept of creative and critical thinking and will help researchers to take further investigations in these important areas of thinking. The developed creative and critical thinking test will certainly help the reader to understand one's own ability to think creatively and critically. The lesson plans demonstrated are easy to transect in the classroom. The tools and strategies help teachers for teaching thinking using content at various stages from primary to secondary level. Teaching content followed by thinking activities will certainly bring change in students' ability to learn and think with the content and ultimately improve their ability of thinking creatively and critically.