Menstruation
In order to trigger students' thinking, this teacher posed an overarching inquiry question (which lacks a conclusive theory) to them and tasked them with formulating their own theories about the question.
Crystal was introducing to students the topic of the menstrual cycle, as part of the larger theme of sexual reproduction in humans.
She decided to pose to them an overarching question on KF (Fig. 1): "Instead of menstruating every month, why is the uterine lining (endometrium) not sustained continuously throughout the life of a woman from puberty to menopause?" She provided students with readings as well as some guiding questions to stimulate their thinking, e.g., Why is there a need for the menstrual cycle? What is the uterine lining used for?
Fig. 1. KF view 'Menstruation'
Consequently, due to time constraints, Crystal explained to students the four theories put forth by the readings she provided to them. She instructed them to choose and explain which theory out of the four, in their opinion, best answers the overarching inquiry question, and to explain the reason(s) behind their choice.
Model of Cells
In teaching her students about cells, this teacher used a diagram of a micro-organism which contains features of both animal and plant cells, and which her students have never seen before, to stimulate their thinking and generate curiosity.
Engel was teaching the topic of Cells to her students. Previous lessons had already equipped the students with background knowledge of plant and animal cells, but Engel decided to further elicit students' thinking.
She found a diagram of a Euglena cell, which contains features present in both plant and animal cells, but is neither of them; it is a micro-organism (protista) which the students do not learn about. She presented the diagram to students, curious to find out how they would classify it and the reasons behind their choice.
Students first penned down their thoughts and questions about the Euglena cell on paper, which were then transferred online to KF (Fig. 1). Engel classified students notes into four groups: those who thought it was an animal cell, plant cell, both an animal and plant cell, and neither an animal nor plant cell. Consequent lessons consisted of discussions about students' ideas and questions on KF.
Fig. 1. KF view 'Euglena'
At one point, Engel selected a promising question posted by a student “Is it possible for a plant cell not having cell wall?” for her students to build on in a new KF view (Fig. 2).
Fig. 2. KF view 'Is it possible for plant cell not to have cell wall?'
Cells and DNA
Two teachers got their respective students to conduct an experiment on extracting DNA from strawberries, so as to incite their curiosity and interest in the topic of cells and DNA.
Two teachers, Mrs Raj and Mr Mong, aroused their students' interest in the topic of cells and DNA by having them conduct an experiment about extracting DNA from crushed strawberries.
Briefly, the experiment involved smashing strawberries, adding extraction liquid (made of detergent, salt, and water), filtering the mixture, and adding rubbing alcohol to the filtered strawberry liquid. The resulting white precipitate/residue (strawberry DNA) that appeared on top of the strawberry mixture (Fig. 1) triggered student's curiosity as to what it was.
Fig. 1. Result of the strawberry DNA experiment.
The following lesson, the teachers initiated and facilitated discussions on KF with their respective classes (Figs. 2 & 3). There were plenty of initial questions regarding the experiment, which were built on and improved, such that students' discussions on KF in consequent lessons revolved around the main concept of cells and its functions.
Fig. 2. Class 1A KF view 'Cells and DNA'.
Fig. 3. Class 1B KF view 'Cells and DNA'
Acids and Alkalis
This teacher piqued his students interest in the topic of acids and alkalis in two ways: first, by asking them to bring substances which they thought was acidic or alkaline to class; secondly, by getting students to conduct an experiment using dragonfruit juice.
The teacher Kelvin was to teach two classes (2A & 2B) about Acids and Alkalis.
He first piqued his students' interest by asking them beforehand to go home and think about what substances in their daily lives are acidic or alkaline, and to bring a small sample of a substance that they thought was acidic or alkaline to the next lesson.
That following lesson, Kelvin had students conduct a trigger experiment on using dragonfruit juice as an indicator to test the pH of certain liquids. He first demonstrated how to extract the dragonfruit juice (this involved mashing and filtering the pulpy residue) and how to test the dragonfruit juice indicator in solutions of different pH (i.e., using droppers, observing colour changes). Students proceeded to conduct the experiment in pairs.
In subsequent lessons, Kelvin facilitated students' insightful discussion on KF (Figs. 1 & 2) regarding the experiment, indicators, pH, acidity and alkalinity.
Fig 1. Class 2A KF view 'Acids and Alkalis'.
Fig. 2. Class 2B KF view 'Acids and Alkalis'.
Menstruation
Instead of menstruating every month, why is the uterine lining (endometrium) not sustained continuously throughout the life of a woman from puberty to menopause?
The theory formulated by Crystal, the teacher, is that it would require a lot of energy to sustain the endometrium continuously, and from an evolutionary point of view, this is not very efficient for the body.
In order to guide students towards an explanation for this question, Crystal provided guiding questions: Why do women undergo menstruation? What is the uterine lining used for? What causes the uterine lining to grow and thicken? Why can the uterus be a good environment for bacteria to grow? How can it affect the woman when microbes grow in the uterus?
Here is the KF view generated:
Nutrition in Humans
Is faeces a type of excretion?
The question led students to think about what excretion is. They came up with many other questions such as "Is faeces edible and is urine drinkable?" Students went on to find out the components of urine and faeces and whether they contained any useful nutrients that could be utilised by the human body.
Enzymes
Students started off the topic on enzymes with an experiment of yeast and hydrogen peroxide, but without knowing the contents of the experiment.
The enzyme catalayse in yeast cells catalysed the breakdown of hydrogen peroxide into water and oxygen gas, resulting in bubbles formed. Students were allowed to smell and hold the test-tube, and using their observations, they were asked to provide a hypothesis of the contents in the test-tube.
