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How, then, do the individual phases of the teaching look?
We start by motivating the students – with some problem, some mystery. It is useful to include a motivational experiment or video.
We start with a motivation - give a problem, a riddle. A motivation experiment or video may be useful.
During the lesson, the students follow the following steps:
I don't understand something, I'm interested in it, I'm solving a problem I ask myself how I should understand this.
I try to find out whether there's someone else who'd understand it.
I state a hypothesis
I verify whether the hypothesis hold – I inquire and experiment I confirm the hypothesis
I refute the hypothesis Figure 1 shows the principle of the IBSE method (simplified).
Figure 1: Circle of inquiry-based education
IMPLEMENTATION OF INQUIRY-BASED APPROACH IN CHEMISTRY TEACHING
If we want to research how does the use of IBSE influence the students' approach to chemistry and scientific subjects in general, we need sufficient amount of materials that would allow implementing the inquiry-based approach in the chemistry lessons. Table 1 shows some examples of themes and problems created for them.
Table 1: An overview of themes and problems from general and inorganic chemistry
Chemistry curriculum themes Problem
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Density of Substances Floating Egg
Mixtures and Their Separation Help Cinderella!
Oxygen and its Compounds Liver and Oxygen
Carbon Dioxide and its Properties Spewing Volcano Calcium Carbonate and its Reaction with Acid Indecent Egg Active Charcoal and its Properties Underwater Volcano Speed of Chemical Reactions Fast and Faster Let's have a look at the theme "Carbon Dioxide and its Properties":
The "Carbon Dioxide" theme will be introduced by the experiment "Spewing Volcano". We shall use baking soda, vinegar, detergent and food coloring for this experiment. In the following experiment, the students are asked to suggest how to prove the presence of carbon dioxide and verify its properties. There are many properties of carbon dioxide they can verify experimentally – that it forms acids, how dense it is, that it's a gas, that it doesn't support combustion, etc. The chemicals students use are vinegar and sodium bicarbonate, so this experiment as well uses student-safe chemicals.
The lesson starts by the teacher asking the students: "What do you know about the carbon dioxide?" The students write whatever they come up with. They usually mention the following knowledge about carbon dioxide: it's a gas, people breathe it out, it's formed during combustion, it plays a part in photosynthesis, it doesn't support burning, it forms acids, it's heavier than air, it's colorless, etc. Following this, each group of students – after discussing this with the teacher – chooses one of these characteristics, as long as it can be verified in the conditions of the school lab. When the students select a characteristics of carbon dioxide to be verified, they also get hints from the tools the teacher puts in front of them. This could be for example a candle or a wooden skewer, which could lead the students to an experiment to verify that carbon dioxide does not support burning.
The students have to suggest an experimental procedure to verify this particular property or characteristic of the gas, based on the tools they get. The results of the student experiments are recorded on a sheet. The conclusions on the student sheets show that the most appreciated part is the ability to work in a completely unconstrained way, to use their existing chemistry knowledge and to suggest their own experiments. There are some problems with deriving general conclusions and dividing the work among the group, but the students improve with time.
We'll give a short description of other problems as well.
In the first problem, "Floating Egg", the students put an egg in two solutions which don't seem to differ in any way. In one solution (water), the egg sinks, in the other (saturated salt solution), it floats. Afterwards, the students solve several problems on the worksheet which should bring them to the basic hypothesis: that the solution densities are the key to the solution. Afterwards, they will suggest an experiment that would prove their conjecture right. The problem can be made more attractive through the use of food coloring.
"Help Cinderella!" is a problem which concerns itself with methods of separating mixtures. The students are given a mixture of salt and pepper and their goal is to separate these components. The advantage of this problem is that the students are absolutely free to suggest various experiments. If they don't succeed at first, they will evaluate their results and determine how to improve the procedure for next time. The problem can be expanded by adding oil as an additional mixture component.
The preparation of oxygen using liver has a very interesting motivational part. It makes use of the catalytic dissociation of hydrogen peroxide, but instead of using the usual manganese heptoxide as a catalyst, it uses the enzyme catalase that is present in blood and liver. The liver is mixed with some water, and hydrogen peroxide is added. The reaction is extremely rapid, creating foam of precipitated proteins. After the foam is removed, we can prove that oxygen was produced by igniting a smoldering wooden skewer. The students are supposed to suggest which substances are produced and perform an experiment that would verify their hypothesis. During the experiment, the students will discover the importance of the enzyme catalase as a catalyst. As we know, the spontaneous dissociation of hydrogen peroxide takes more time and wouldn't achieve concentration of oxygen necessary for the skewer to ignite. In the end, the students repeat the experiment using manganese heptoxide as a practical verification of the fact that various substances may be used as catalysts, without affecting the resulting products.
The problem "Indecent Egg" is based on the fact that carbonates react with acids. After the egg is pickled in vinegar, its solid carbonate shell dissolves, so the egg is now protected only by the elastic membranes. During the pre-lab preparation, the students will get acquainted with components of the egg shell and with the reactions
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of the gas produced by the reaction.
The "Underwater Volcano" is a motivational experiment based on different miscibility of cold and hot water. Hot water with food coloring is prepared in an Erlenmeyer flask, which is suspended on a string into a larger vessel filled with cold water. The students' goal is to get clean water through filtrating the mixture of colored water and active charcoal.
The problem "Fast and Faster" concerns itself with the course and speed of chemical reactions. The students gather information while working with the text and, in cooperation with the teacher, discuss various factors that can affect the speed of chemical reactions. Such factors are, for example, the temperature of the reaction mixture, reactant concentration, or the surface of the reacting substances. The students will select a factor they are going to verify and suggest an experiment to support their hypothesis. The students use zinc and hydrochloric acid during this activity.
With the standard approach, the students are more passive: the teacher gives them precise procedure for the experiment and they complete it, step by step. IBSE forces the student to have much more active approach to finding the answers. This type of teaching is more demanding for the students and not all of them are able to deal with it from the beginning, but they will interactively absorb the knowledge and connect it to other sensations.
This will improve the memorization of facts. However, at the same time this approach leads not to memorization learning but to understanding of problems. The students' own experiences with experiment and practical presentation of a specific characteristic teaches the students to connect the acquired facts and move from understanding the individual steps to understanding the whole.
EVALUATION
We use the self-contained evaluation material Diagnostické nástroje na podporu výskumne ladenej koncepcie v prírodovednom vzdelávaní (Bergman, 2013) which supports the effective implementation of research-oriented approach to the education in scientific disciplines. Bergman prepared, among other things, evaluation sheets which track the teacher's role, the students' activities and their records, and simultaneously enable him to determine how much do the lessons correspond to the IBSE requirements. The various sheets are focused on the role of the teacher or they evaluate the students' activities and records.
Table 2 shows a part of the evaluation sheet "Student Activities"
Item Explanation and examples Evaluation
Did the students see solving of the research question as their own, even though you might introduce the question to them?
The students consider the question their own if they are able to explain what they want to do or find out in their own words.
Yes No Inapplicable
Were the students' assumptions based on their previous experiences?
The students were able to explain their assumption, even when it was imprecise or incorrect, thus showing that it wasn't a mere guess.
Yes No Inapplicable
Did the students participate in the planning of the research?
The students themselves suggested how to resolve the problem and how to answer the question, although they sometimes needed help to resolve the details.
Yes No Inapplicable
Do the students suggest correct research procedures that include variable control?
The students suggest, during their research activity, which variables need to be manipulated and which should be kept unchanged.
Yes No Inapplicable
Did the students realise the research on their own?
The students gathered data on their own (through direct observation of the objects, measurement or from secondary sources) and used them during arguments – they were not merely watching other students gathering data.
Yes No Inapplicable
CONCLUSIONS
In my research work, I observe the influence of IBSE on students and its effect on their knowledge and their ability to understand the principles of chemical processes. At the same time, however, I'm trying to verify that the application of IBSE is able to motivate the students to study chemistry and have positive effect on their
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perception of the subject. I.e.: will this arouse interest in science and phenomena encountered in their everyday life? Use of simple experiments will also support the students' ability to work metodologically when solving problems, their critical and logical thinking will be developed, and they will also get into habit of verifying information and its sources.
REFERENCES
Bergman, G. Diagnostické nástroje na podporu výskumne ladenej koncepcie v prírodovednom vzdelávaní.
Trnava: TYPI
UNIVERSITATIS TYRNAVIENSIS; 2013. ISBN 978-80-8082-792-2
Čtrnáctová, H., Banýr, J. Historie a současnost výuky chemie u nás in Chemické listy. Roč. 91, 1997, s. 59-65.
Mayer, R. (2004). Should there be a three-strikes rule against pure discovery learning? The case for guided methods of instruction. American Psychologist, 59 (1), 14-19.
Rocard, M., Cesrmley, P., Jorde, D., Lenzen, D., Walber-Herniksson, H., Hemmo, V. Science education NOW:
A Renewed Pedagogy for the Future of Europe.
Tomášek, V., et al. (2007). Výzkum TIMSS 2007: Obstojí čeští žáci v mezinárodní konkurenci? Praha: ÚIV.