Revisiting “The Joy of Teaching”

I published in September, 2018  a post on “Joy of Teaching”. Today, on this Teachers Day, I thought of revising this post once again. If you havent read the original post, then do read it here

Today, I am also writing this post to express my deep condolences to the family of my Teacher and Former Colleague, Professor Rashmi Patil.

Prof Patil expired in Mumbai on September 1. Her sudden death was a shock to all of us. Professor Patil taught at the Centre for Environmental Science and Engineering (CESE) at IIT Bombay.

I remember days at CESE IIT Bombay where I was a lecturer in 1984. All of us, as teachers, used the blackboard then with a box-full of chalks to “construct” what we wanted to say and “communicate” to the students. Use of Overhead Projector (OHP) and the plastic foils was just emerging.

Using the blackboard required teachers thorough understanding of the subject, confidence or the command to convince and of course the creativity. There were no “props” like the plastic foils where the content to be spoken was already written. You needed to ensure that your writing on the blackboard is neat and in the right font size so that it can be read by a student who is sitting on the last bench. You also needed to draw well, especially the diagrams and use chalks of assorted colors for the required emphasis. A big advantage of blackboard based teaching was that it made the students write and take their own notes as you erased the board once done with your point or topic. Today students are not simply writing! Professor P Khanna, who was at CESE and later at National Environmental Engineering and Research Institute (NEERI) as a Director was a great “blackboard teacher”.

OHPs are now replaced by LCD projectors where teachers use PowerPoints, animate the slides and insert videos to make teaching interesting. This is great. But still, I find writing on the blackboard very effective and challenging.  You feel more of an Actor in the classroom as your voice modulation, pauses, movements across and towards the blackboard matter.

When you draw a stretch of river and show discharge of untreated wastewater and then “narrate” what happens to the Dissolved Oxygen (DO) profile by drawing the DO-Sag Curve, you essentially build the “situation” step by step. You speak as you draw. The communique to the student therefore “brews”. Its not the matter like instant coffee!

Well you can do this today rather dramatically with the help of animated PowerPoint slides. But to me developing the situation real time on the blackboard is like offering a freshly squeezed juice as against providing a canned juice! The fizz of the subject is simply lost when you have something already prepared or cooked that you many a times “mechanically” deliver.

I remember each time I taught the DO-sag curve, the visualization on the blackboard was different – as ideas came to my mind on “real time” i.e. from the thin air surrounding me.   In this process, many “lateral” questions used to come up. I would sometimes show a case of DO Sag going below 2 mg/l of and then question the students whether the first order kinetics of BOD degradation was still valid.  In some occasions, I would invite a student to draw DO sag due to discharge of a non-point source such as fertilizer laden runoff from agriculture fields. Posing these situations would make students a bit uncomfortable, but then such “expansions” created ground for me to slowly build the complexity of water quality modelling. We transited, and casually so, beyond the basic equation of Streeter and Phelps of 1925. This matter was however put rather logically and humbly!

When we talk about complexity, teaching subject like environment, requires out of the box thinking on part of the teacher and an innovative strategy. The sheer complexity and uncertainty of environmental science is really exciting to teach. Nexus is the crux that needs to be “taught” and that is where a teacher is needed to introduce the relationships, generate discussions and motivate building of scenarios. It’s the free thinking that is to be introduced. The cross-connect in teaching environmental management of today and for tomorrow is to emphasize on the nexus. I hate teaching in silos like air pollution, water pollution, solid wastes etc.

Nexus is best communicated through story telling. You don’t start teaching atmospheric chemistry of smog formation first – instead you tell the story how the flights to Los Angeles  in the winter are significantly delayed. And how these persistent delays affect people’s lives and the economy. Then ask why does this happen? The story used to “compel” the students to unfold the science behind the smog episodes and so the relevant chemistry comes in.

You tell the students a story where recycling of plastic was used to make toys for toddlers. Isn’t recycling of plastic waste a clever idea? You ask the students. You then tell how the recycled plastic  could lead to adverse impact on the neurological functions of the toddlers who love to chew these recycled toys ! These potential adverse impacts were understood much later.

Well these adverse impacts could well be questioned and argued. The probable reason could  be use of flame retardants in the used plastic that remain “unabated”. The story illustrates the case of ”irresponsible recycling” and throws up several technical and policy related matters related to use of safe chemicals for a discussion.

A teacher is needed to tell such stories in the right or clever sequence pointing out the science, economics, social concerns, policies and of course the politics behind. Imagine if a teacher uses a bank of 30 such well identified and researched stories to “teach” students a full course on environmental management. While stories open up the minds and makes one aware of the realities; the underlying science is read by the students as essential supplements – but not in the class but “off-line” – by reading notes, research papers on googling the web.  I enjoy teaching when I run a course full of stories. And indeed, this is close to the “flip” method of teaching. This method on virtual platform will receive more attention given the challenge of COVID-19 pandemic.

But teaching does not have to be only in the class room. A lot happens when you take students on a field trip that is well planned. These field trips or “yatras” provide great experiential learning opportunities, in a group, and often in an implicit manner. So, if you organize a field trip to Ralegaon Siddhi (a transformed village in the State of Maharashtra in India), students understand the linkages to the development and environment and the complexities. They experience the story.  Perhaps in a course of 36 lectures on environmental management, spending weekends at 4 interesting locations for such “experiential learning” will be very effective.

Recently, I was delivering lectures for Master Trainers for Indian Railways. These Master trainers were expected to teach the subject of Environmental Management & Sustainability. These lectures helped me to express my “joy of teaching”.

See below links to my 7 videos in the form of a playlist that may interest you.

[To toggle between the 7 short videos, click on the playlist icon on top right corner of the video playback window as shown in the image here. On clicking the icon, a drop-down with a list of 7 videos will pop-up. You may select any video of your choice to play.]

Do send me your comments. Remember – its a playlist

Let me now end this post sharing with you one of my memories with Prof Rashmi Patil.

It was 1973 and I was an undergraduate student at IIT, Bombay. Prof Patil was then a demonstrator in the Physics Laboratory. She was very young, must be around 30 in age. In the final exams, students were allotted experiments to perform and I was given the experiment to find the value of G – acceleration due to gravity.

I was so delighted to get this experiment as the answer was already known as  9.8 m/s2 .  I had to just swing the pendulum, record the time and find G using a formula. So, I happily stepped out to the balcony and was watching the passers by. There was no hurry.

Prof Patil came to me and smiled (she always had an infectious smile). She softly said “Sometimes you already know the truth, but you have to experience it to understand how you cannot still reach to it. Your pendulum experiment is not going to give you the precise value of 9.8, despite your best efforts. So give a try and learn why.”

She was absolutely right.

Teachers have a subtle way to say so many things that are unspoken.

My salute to Professor Rashmi Patil

A photo, perhaps in 1988 at CESE. L-R Prof Patil, Me, S K Gupta and Shirish Naik. We used to have chai and batata wada sessions at Prof Patil’s room every day. Today, faculty seldom meet for a friendly chat. They are like islands.

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  1. Very well written Sir! So many memories flashes back on this day and after reading your blog. Madame Patil will be greatly missed.

  2. Thank you Prof. Modak. I cannot express enough gratitude to you and the amazing teachers we had at CESE, Prof Rangnathan, Prof. Natrajan, Prof. Viramani, Prof. Asolekar, Prof. Joshi and indeed Prof. Patil. what I learned in those 18 months was much more than the technical knowledge you infused in us. It changed my outlook completely and it accompanies me till today, and especially when I teach.

  3. This made me very nostalgic. Remembered the days of CESE from 1990-1992. The news of sad demise of Mrs. R.S.patil is still fresh and saw the pic. Yes I always saw her flashing that infectious smile… As always a fabulous narration and read. Thanks a lot Dr. Modak sir

  4. I loved the story. I used to teach a course on water management with more than thirty stories in a semester with few field visits. It was interesting experience.
    Thanks for sharing.

  5. An apt tribute to a Teacher, by a Teacher on Teacher’s Day.

    I too swear by a blackboard & chalk when I am trying to learn something new.

  6. Sir YouTube videos are not available.

    And happy teacher’s day to you.
    I just fond of environmental engineering since my engineering days , though it’s not possible me to learn environmental engineering academically but i do follow your blogs regularly and find it so enlightening. Thanks you so much for your efforts.

  7. I enjoy reading your blogs. Feeling sad to know about sudden death of Dr. (Mrs ) R. S. Patil. May her Soul rest in peace. Omshanti!!!

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