An experiential inquiry-based approach to teaching science may not only strengthen conceptual understanding, but also go beyond topic-specific learning outcomes to help students develop important skills in the practice of science.
These include observation, critical questioning, abstract thinking, verbalising gaps in understanding (self-awareness), experimentation, and collaboration (practical skills). Can we deepen such learning experiences by offering space for students to work with a sense of mindfulness and beauty?
To explore this question, I introduced the fundamentals of chemical reactions to Grade VII students using the art of lithography (see Box 1). I knew that this kind of hands-on work was likely to capture their attention.
Can integrating the art and aesthetics of lithography in an inquiry-based approach to chemical reactions strengthen student understanding and help them develop important skills in science? What questions, discussions, and digressions emerge from such an approach? What role does the teacher play in facilitating such explorations?
My decision was also guided by the fact that the students in my class had been exposed to a variety of artwork, and enjoyed creating art themselves. And some of them had shown a capability for the practical skills needed for this kind of artwork.
Box 1. What is lithography?
The term lithography is derived from two Greek words — ‘lithos’ meaning ‘stone’ and ‘graphein’ meaning ‘to write’. Based on the immiscibility of oil and water, it uses simple chemical processes to create images on a flat surface.
In its simplest form, an image (called the positive image) is drawn on a flat rocky surface (like, limestone or marble) with a hydrophobic (water-repelling) medium (like, wax crayons, oil paint, or nail polish).
An aqueous acid solution is used to etch off the negative image (the unpainted parts of the surface) to impart 3‑dimensional features to the surface. One could also attempt to combine the visual effects of both positive and negative images while choosing a pattern for etching.
Aims of the activity
One aim of this activity was to strengthen an understanding of important concepts in chemical reactions. Students in this age group had not yet been introduced to the atomic structure of matter but showed a factual understanding of chemical reactions in terms of the properties of substances and some preliminary ideas about acid-base reactions.
While some students seemed to appreciate topics involving the nomenclature and classification of matter, quite a few did not relate to the abstract nature of these topics. All the students were quite curious to observe some of the chemical changes that they had heard and read about.
The other, broader, aim was to help students develop a propensity to work and inquire together, and to explore concrete experiences as a scientist would. Such activities inevitably draw out interesting questions and comments from students.
While the plethora of questions addressed to the teacher can sometimes be daunting, I feel that only some of these questions need answers. Some others may need some refinement by the teacher. But many questions could be left, perhaps with some pointers, with students for their own exploration.
For the teacher, this last category of questions can be seen as an invitation to participate in the way students make sense of things. They reveal the nature of the student’s mind that is simultaneously observing, questioning, trying to offer explanations, and connecting their thinking to everyday experience.
I started the activity by introducing students to the marble slabs and sea shells that we were to use as our base material (see Activity Sheet I attached at the bottom of the article). I also explained the overall process and the expectations involved (see Fig. 1).
During steps 1 and 2, I invited creativity by encouraging students to work in groups and use nail polish to paint any shapes they agreed upon on the surface of the base material. The teacher may need to ensure that there is good understanding and alignment within each group on what to draw.
Step 3 was a teacher-led phase. Each slab was immersed in an aqueous hydrochloric acid solution used as an etchant and kept in a shallow transparent plastic pan to allow us a clear view. The students were encouraged to observe the entire process and record their observations and any thoughts that occurred to them.
In steps 4 and 5, the etched sample was washed with plain water and the paint was wiped off with acetone. Students were then able to see, touch, and feel the etched surface. Each group was encouraged to observe and correlate the effects of their drawings on the etched marble surface.
From a purely aesthetic point of view, they were also encouraged to repaint the figures as they wished, using watercolour, crayons, or ink to give finishing touches to their samples (see Fig. 2).
Trigger questions: Connecting science processes to experiences
Throughout the activity, but particularly during its last stage, students came up with many questions, observations, and new ideas to implement in a second run. It was a joy to watch them discuss these with each other, and make new connections. Here are some of their questions and comments along with some notes on their background, and the kind of learning they may lead to:
Question: “Can we use citric acid or vinegar to etch designs on any stone? Can I use this method to make stone jewellery in the holidays?”
I pointed out that this method may not be appropriate for ‘any stone or metal’. I also indicated that this was a great idea, provided students could use this method of etching at home in a safe manner.
Towards this goal, I suggested that they could start by using kitchen vinegar with some citric acid on marble tiles or chalk stone surfaces.
Question: “How fine can the carvings be? Can I draw hair-like lines?”
The student was trying to contrast this chemical etching technique with a stone carving process that she was familiar with. Having observed the
effort (energy) it takes to use a chisel to carve a slab of stone, she was wondering if the removal of matter from a marble surface through chemical etching also needed some energy. My response was to convey that chemical processes also involve work at a microscopic level.
Question: “What are those whitish powdery things? Is that marble powder? How small can we cut a piece of marble so that it still is marble?”
Here the student was referring to a powdery white substance that was formed during the reaction. She was unsure if this powder came from inside the marble piece. This question brings to mind early scientific debates about the nature of matter at microscopic scales. Atomists like Democritus used pure reasoning to suggest that there was a lower limit to dividing a grain of sand while retaining the properties of sand.
Question: “Where does the etched-out marble vanish? What would happen to the marble if we leave it inside the acid solution for a long time?”
This student wondered if it were possible for the acid to “eat up” the whole slab if the reaction was allowed to continue long enough. In other words, she wanted to know if this process would ever stop by itself (see Box 2).
Box 2. Would acid etching stop by itself?
We decided to explore this possibility by letting this experiment continue for the duration of an entire class. The students observed that the rate of appearance of bubbles (that appeared at the start of the reaction) showed a gradual slowing down and stopped completely after about 15 – 20 minutes. They also observed that by this time the marble slab looked porous and diminished. Student groups were invited to discuss this observation and offer some explanation for it.
Two interesting responses emerged:
a) Just like the solubility of sugar in water, there may be some limit to how much marble gets dissolved by acid;
b) Since the acid and the marble are in the same solution, the marble may have mixed with the acid, making the acid more and more impure. This might explain the slowing down of the reaction.
One can see these very natural and logical connections the students had arrived at while trying to explain their observations (also see Teacher’s Demonstration: Is Acid Etching Self-limiting?).
One may pause here and wonder what brings about such reasoning in preadolescents. Is it exposure to scientific literature, discussions, or just a developmental outcome? Is this an outcome of early age involvement in observational activities? Are some social factors also involved?
Perhaps multiple factors may contribute to the development of such intelligence. Such instances seem to suggest that it may be possible for young minds to discover the fundamental questions of science even within the constraints of today’s classrooms and syllabi.
Comment: “As long as the acid solution touches just the surface, etching should continue. The entire slab need not be inside the solution.”
This comment came from a student who was interested in using less acid for the activity (see Box 3).
Question: Is it possible to ‘anti-etch’ or ‘grow’ something on the surface of the slab?
One group explored the possibility of drawing their “story” by combining both negative (etch) and positive (anti-etch) images on the same slab. While a negative image adds depth to the figure, a positive image renders an upward projection (see Fig. 3).
They described this as an interesting challenge since they had to shift their attention between the two drawing techniques (see Fig. 4). While most of them seemed to like experimenting in this way for the fun of it, a student questioned if it was possible to combine both the techniques in a single figure.
While this response was not directly related to a chemistry concept, the student’s ability to sense this new possibility is an example of a creative act in the learning process — a trait to be encouraged.
- Discussion as a way of learning: Interesting discussions kept happening intermittently throughout the activity (see Box 4). The extent to which the students were interested in each other’s questions, suggestions, and explorations was quite remarkable.
These discussions were broadly about the nature of matter at microscopic levels, explaining an observation, sharing an insight by a student, and so on. It was as if the group had a mind of its own! Many students showed increasing self-awareness, in the sense that in attending to others’ ideas and explanations, they became more aware of their own thinking. It was also interesting to see how some students were able to bring the class to a common understanding.
- Expanding and deepening connections: Such an integrated, inquiry-based teaching style allows many opportunities for deeper mental connections to be formed. For example, this activity allowed multiple possibilities of connecting various concepts while offering interesting digressions (see Fig. 5). Many potential digressions may be explored to break the monotony of the class.
I feel that such contextual digressions bring about a reflective mood and may help in forming deeper mental connections.
Areas as diverse as arts, games, and cooking can offer many opportunities to teach science in a hands-on and fun-filled manner. The challenge for a science educator is to identify aspects of these areas that lend themselves to understanding specific concepts in the science curriculum and to convert them into grade-appropriate activities in a creative manner. It is my submission that such science activities can help sustain the attention of a group without much coercion.
Box 4. A sample of interesting discussions:
On the nature of the acid:
Student A: “Sir, the acid is in the water solution. But why does the smell hurt so much?”
Student B: “Perhaps the acid is evaporating from the water.”
My response: “Yes, some acids evaporate from the solution. In general, the solution may contain substances that evaporate at different temperatures and at different rates. In this solution, hydrochloric acid evaporates more easily than water. That is what is hurting your sense of smell. It is the smell of hydrochloric acid in the air.”
Student C: “You had mentioned that many acids are naturally found in gaseous form. Does this make it easier for such acids to escape from solutions?”
This student was trying to apply the ideas of acids and bases introduced during earlier classes to a new question. This included the understanding that fire, which is a chemical reaction, tends to separate acids and bases — air takes up acids in the form of emanating smoke, and the earth (soil) takes up bases in the form of ashes.
Thus, many acids (like CO2 and HCl) are found in gaseous form, and many alkalis (like CaCO3) are found in soil. It also drew from the understanding that water dissolves both acids and bases, and the reaction of these two solutions is called a neutralization reaction.
On the reaction products:
My question: “What do you think about the white powdery substance that is created when the reaction is going on? What could that be?”
Student D: “It must be marble powder.”
Student E: “But when we break a regular marble slab, the powder does not come out like this. It must be something else.”
Student F: “Is it something like rust in the iron bar experiment? Rust is different from iron, and did not exist before rusting. ”
Recognizing the formation of new substances is key to understanding any chemical process.
On the hydrophobic nature of substances:
Student G: “Sir, why is it that only the unpainted area reacts to the acid? Why does the painted area not react to it?”
My response: “Observe the surfaces in the painted and unpainted areas that are in contact with the acid. In the painted areas, the acid solution is in contact with the nail polish. So what do you think the nail polish does to the painted area?”
Student H: “Oh okay… So, the nail polish makes the reaction slower? That may be why the unpainted area gets etched faster.”
My response: “Some substances like to ‘stay away’ from water even if they are dropped in water. Substances with this property are called ‘hydrophobic’. Some examples of such substances are oil, nail polish, oil paint, fat, grease, and wax.”
Student H: “So if the water in the acid solution has to touch the marble surface, it has to go through the paint, which it cannot do because of the nail polish. Right?”
My response: “Yes, that’s right.”
Student G: “But it is the acid which etches, and not water.”
Student H: “Buddy, the acid is contained in the water. If the water cannot touch the surface, how can the acid touch it?”
By increasing avenues for individual exploration, this approach can also be more effective in getting students with diverse interests, abilities, aesthetic sensibilities, and skill levels involved in the learning process.
In addition, it empowers students with the ‘art of exploration’ and imparts a ‘sense of ownership’, both of which bring vitality to the learning process (see Box 5). Students not only learn the required concepts in chemistry, they tend to cherish such experiences till long after.
Box 5. Some suggestions for the teacher:
- Encourage students to observe things that they may have overlooked, and to probe some of their observations more deeply.
- Be open to co-approach ideas and concepts, and be tentative about them. This involves a capacity to be attentive and tolerant about how ideas take shape in students’ minds, and then come to a common understanding.
- Pay close attention to the exchanges that take place within each group since it can give insights into the way students think on their own and in a group. Several ideas for experiments to extend the activity may emerge during these exchanges.
- Use the blackboard to draw mind maps to show the connections that students identify between the activity and chemistry concepts in their curriculum. These may include chemical reactions such as neutralisation (identifying the reaction and reaction products), the chemical composition of marble and chalks, weak and strong acids, etc.
- Through this activity try and bring about a ‘fun, but still relevant’ element in learning.
- It is useful to plan classroom activities that encourage an understanding of science concepts through art and aesthetic work.
- Activity-oriented classes allow a multi-sensorial and ‘fun’ approach to learning. Students get an opportunity to relate to concepts through their own observations, feelings, and experiences. This may aid better attention and deeper learning.
- It is important for the teacher to lead the class, but not at all times. If student groups can be encouraged to work together, they listen and learn from each other; examine, extend and trim down each other’s reasoning; and, sometimes, bring the majority of the class to a common understanding.
- Such an approach may allow the teacher to facilitate the development of some psycho- emotional skills that are crucial to the practice of science. These include observation – listening– thinking, working together, intelligent guesswork, as well as the ability to make sense of information and make connections.
How do we integrate the art and aesthetics of lithography in an inquiry-based approach to chemical reactions? How does this approach strengthen student understanding? What skills in science does it help them learn?
Join us in exploring these questions with Ranjit Kumar Dash and Mala Kumar.
I would like to thank the teachers, staff, and students who have sparked ideas for the making of this module through many casual discussions. I would also like to thank the student groups who participated in this journey, and shared their perspectives. It is my pleasure to thank Mr. Alok Mathur (Rishi Valley
School), Dr. Radha Gopalan (Azim Premji University), and Prof. Arnab Datta (IIT Bombay) for going through the article critically and offering useful comments for its improvement.
Note: Source of the image used in the background of the article title: A collage of triangles. Credits: Ranjit Kumar Dash. License: CC-BY-NC.
- Wikipedia contributors. (2022, July 3). Lithography. In Wikipedia, The Free Encyclopedia. URL: https://en.wikipedia.org/w/ind….
- Hague Circle — International Council for Steiner Waldorf Education and the Pedagogical Section at the Goetheanum. Vertical Curriculum — Chemistry, Waldorf Resources. https://www.waldorf-resources.org/vertical-curriculum/chemistry
- Mitchell, David S. (2004). The Wonders of Waldorf Chemistry from a Teacher’s Notebook, Grade VII-IX. AWSNA Publications, New York.
About the Author
Ranjit Kumar Dash is a teacher at Rishi Valley School, Andhra Pradesh. He is passionate about bringing together simple experiments, hands-on activities, various forms of artwork, and learning from nature to make the teaching and learning of science interesting.
He can be contacted at email@example.com