A passion for teaching science

Dr Debapriya Mukherjee   
My experience on the variety of activities in Central Pollution Control Board and frequent interactions with trainee from environment laboratories and students at school level have made me obsessed with four things: teaching science, doing science demonstrations, assessing chemical behavior of pollutants in environment  and research in it, and hobbies like vermi-composting, handicraft from water hyacinth, organic farming and aquaponics.  Dr Samar Bagchi, ex-director of BITM , Kolkata  and I met once  at a science teaching seminar  in Kolkata  about 4 years ago and learned that we shared passions for the above four things.
 What I have realized is that as a teacher I must have congruent passion and conscious politeness and exude the feeling of my joy with my students to compel them to listen without getting bored. I always maintain politeness in my demeanor throughout the period while I am delivering a lecture or answer a questions. Most classes function with a “designated” student(s)  who ask most of the questions. I tell these students they are secretly admired by the rest of the class. The questions are repeated and answered. Then I ask the students on the adequacy of my answers. Finally I thank the questionnaire for helping me teach better. In this way my enthusiasm goes beyond the subject matter and embraces the students as friends. By creating loving ambience I have not only made this class a joy to attend but also this class has become a oasis of friendship.
 During teaching I  am always into my  demonstration room to have fun and do what is  most important to me in my life: teach and share and be totally immersed in my students and my subject because I still remember being bored into catatonic states by some teachers. Many students while imparting training expressed the causes of their failure in understanding basic concept of science on account of rote learning.  Everybody loves hearing stories, and all may astonish about its relevance in a chemistry lecture. I have always told stories at all levels in my lectures. I learned over the years that a large number of the students forgot the subject matter I was presenting, but they always remembered the stories. In this regard it is probably better for the story to be related to the subject matter of the day. I always started a general chemistry course with a full period chemistry demonstration show. This practice is followed while I deliver the lectures on general science courses.  I always want that classroom to be a place where people were having fun, and in which they looked forward to being. Thereby I communicate all the students after demonstrating the “blow up a balloon with yeast”, “bend water with static electricity”, “fire in water”, “magic sand” and many others  that I am here to have fun and enjoy myself. If you happen to learn something while I am doing that, I will be pleased. Otherwise, I might be just a bit sad.
 According to my assessment, a central motivating factor in becoming a chemist/environmentalist is wondering about the nature of the world around us and how it is put together and work. Thereby teachers must inculcate the passion among the students with awe and wonderment about chemistry. One amazing story is  that a soft metal like sodium reacts with a green gas like chlorine to form the ‘‘salt of life.  If we observe this salt with magnifying glass we will see that individual grains of salt are cubic. But the sodium alone flares up almost immediately upon reaction with the water and burns out quickly. Similarly chlorine gas alone is toxic and extremely irritating to the eyes and mucous membrane. Wow! Incredible!
 However the subject of chemistry is in some ways three times harder to learn than say history. The latter basically require mostly memory, while chemistry requires mathematics, memory, and abstract thinking. Balancing a chemical equation needs an understanding of chemical equilibrium, and calculating an amount of product from amounts of reactants requires some mathematical skills. The understanding of the structure of an atom needs visualization and abstraction. But, if one-half or fewer of your general chemistry students are functioning conceptually primarily in concrete terms, then they may be able to answer questions by rote, but not with understanding.
 Finally I refer the wonders of chemical behavior of pollutants in River. The formation of white particles containing high concentrations of Aluminium, silica, sulfate at the confluence of Lukha river at pH4.5 was the major cause of  the blue coloration of river and fish mortality. Many such chemical reactions in water are really incredible and presenting these reactions with practical demonstrations inculcate the passion among the students with awe and wonderment about chemistry. Being overtly passionate about teaching and being willing to show that to your students is the essence of being a good teacher.