Asia-Pacific Forum on Science Learning and Teaching, Volume 8, Issue 1, Article 16 (June, 2007) Kok Siang TAN Using “What if..” questions to teach science Previous Contents Next

Conducting the lesson

Traditionally a lesson on experimental science would commence with teacher talk, student evaluation and then possibly, a confirmatory experimental experience in the laboratory.  Inquiry-based lessons may tweak the lesson structure a bit, with the teacher starting a learning task by asking a question.  For example,

“If you are stranded in the open sea on a small boat, how would you go about making some fresh water to drink from the sea water around you?  (Assuming you have the essential laboratory wares with you.)”

The teacher may then follow up by facilitating a class discussion and end with the teacher summarizing and contextualizing the discussion to fit the curricular requirements.

Mortimer and Scott (2003) in their book, Making Meaning in Secondary School Science, suggested that students should engage in some form of dialogic activity if they are to develop an understanding of a science topic.  In this respect, classroom talk, learning and meaning making would not make strange bedfellows but are essential features in the science classroom that would ensure students gain some impactful learning experiences.

The lesson, which the present discussion is based on, involved both the traditional classroom lesson delivery and the engagement of student dialogic process.   It was conducted for a group of ten secondary three express students (equivalent to grade 8). The students, four girls and six boys, were selected by their Chemistry teacher to attend a remedial lesson on the topic of “Separation Techniques”.  They came from two different classes taught by the same teacher.  The separation technique to be revised in the 40-minute lesson was on “Simple Distillation”.  The author of this paper was requested by their teacher to teach this remedial lesson.  The author (referred to as the ‘remedial teacher’ in this paper) is also a qualified and experienced school science teacher of over 16 years. The proceedings of the lesson are summarized in Table 1.

Approximate Time frame	Learning/teaching events	Pedagogical approach
10 minutes	- Introduction - Importance of separation techniques in chemistry - Example of a technique: Simple Distillation	Teacher talk
10 minutes	- Activity: Students to pose questions - First attempt: Invitation to verbalise the questions (no  students volunteered) - Second attempt: Invitation to write down the questions starting with the words “What if..” (Students were observed to be actively on task.)	Reflective learning strategy: Use of “what if” questions to get students to observe the learning task and generate responses (in this case posed questions)
20 minutes	- Activity: Teacher-facilitated the discussion on the what if questions posed and written by the students on slips of paper. - The slips of paper were collected and each student’s written questions were projected on visualiser and openly discussed by the students with comments and evaluative remarks made by the teacher.  Students were instructed not to write their names on the paper.	Reflective learning strategy: students engaged in meaning making (that is, attempting to answer, critique and perhaps re-phrase the questions so that some relationships can be established among the ideas generated).
5 minutes	- Summary: teacher summarised students’ responses to the learning tasks - Conclusion: teacher concluded lesson with a review of the distillation method	Teacher talk

Table 1: Lesson Proceedings

After the formal greetings and a simple self-introduction, the remedial teacher proceeded to explain the importance of separation techniques in chemistry. He cited simple distillation as an important technique that allows us to obtain a pure solvent or liquid from a contaminated liquid sample (a solution or a suspension).  A fully labelled diagram of the apparatus set up for simple distillation was projected on the screen with the help of a visualiser (Figure 1).  Referring to the diagram on the screen, the remedial teacher then proceeded to explain how the simple distillation apparatus works.  The students were attentive and some were busy taking notes. This segment of the lesson lasted about ten minutes and was totally delivered by teacher-talk.

 

Figure 1.  Diagram of a simple distillation set up for distilling seawater.

 At this juncture, students were invited to verbally ask any question about the apparatus set up.  There was a short pause with no response from the students.  The remedial teacher then requested that they pen their questions on blank pieces of paper.  Again, there were some “thoughtful” actions (for examples, a boy had his chin propped by his hand on the table and a few girls showed contorted eyebrows, all presumably deep in their thoughts).  Most of them stared blankly at the diagram projected on the screen. Again, no one wrote anything. 

The remedial teacher then wrote the following words on the whiteboard – “What if…” and instructed students to begin posing their questions with these two words.  He also added that they could ask anything about the apparatus set up, including the materials, products, reaction conditions or anything that interest them, so long as it was something related to the simple distillation process or apparatus set up. They could ask questions that they know the answers, or questions that they do not know the answers.  No examples were given to the students other than these instructions.

It was observed that students began to pen their thoughts, writing down the questions and raising their heads periodically to refer to the diagram shown on the screen.  It took about ten minutes before most of them became exhausted of ideas and a few started to curiously peek into their neighbours’ work.  The remedial teacher then collected the papers and began to flash them one by one on the visualiser.  For each student’s questions presented, the remedial teacher facilitated an almost spontaneous response from the floor.  Students were observed to be chatty while a few showed amusements at their peers’ questions.  There was a lively contribution to the possibilities raised by the questions, including difficult and unfamiliar situations arising from questions like “What if there is no condenser there?” and “What if the Bunsen burner was replaced by a candle?” (Figure 2)

 

 

 

Figure 2.  “What if..” questions can surface unfamiliar experimental situations