Structural outcome – teaching experiment

This chapter describes the teaching experiment (structural outcome), the last part of the designing process of this study. At the background of the teaching experiment are above depicted teaching model of DC-circuit phenomena (subject matter outcome) (6.5) and talk-activating learning environment (pedagogical outcome) 6.6. The teaching experiment has particularly been constructed to support the empirical concept formation process, and taking into account historical models and the pupils’ general external representations of the DC-circuit phenomena. The role of teacher is active and guiding, but the pupils in a small group are also encouraged to process the external representations via new observations, comparisons and negotiations. Thus the approach used is as described earlier in section 3.4.

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Figure 32 The structural outcome of the design solution: teaching experiment. See also Table 6 for the timetable of the teaching experiment.

Figure 32 includes the structure of the teaching experiment of DC-circuit phenomena.

The teaching experiment consists of five parts; the experiment begins with a preliminary interview, goes on to a small group teaching experiment 1, is continued by an intermediate interview, goes on by the second teaching experiment, and finishes in a final interview.

Interviews

Interviewing the pupils was divided into three phases: a preliminary interview, an intermediate interview and a final interview (see Figure 32 and Table 6). The first interview, the preliminary interview, which took place just before the lessons also included a preparatory sectionfor the lessons. The small group of pupils was interviewed in the preliminary interview.

The subject matter goal of the preliminary interview was to chart pupils external representations of an electric circuit and electric current (see teaching model, section 6.5).

In addition, from the standpoint of learning, the interview was of a preparatory nature Preliminary interview:

Charting the conceptions

of electric circuit and electric current

Small group learning, period 1:

Electric circuit, electric current, and comparing current strength

Small group learning, period 2:

Source voltage and comparing magnitude of source voltage

Application of electric circuit, electric current and source voltage

Intermediate interview:

Testing the learning of electric circuit and electric current

Charting the conceptions of source voltage

Final interview: Charting the learning results of the whole school experiment

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setting up a hypothesis for the electric circuit and the electric current for the first teaching experiment.

Connection cards were used as pedagogical solutions in the preliminary interview Different connections were constructed with the connection cards, which the small group used when discussing the functioning of the electric circuit.

The goal of the intermediate interview was to test the learning of the first period and to chart teaching experiment two. The subject matter goals of the interview were testing the learning of the electric circuit and the electric current. Moreover, the conceptions of the source voltage were charted. The connection cards were also used in the intermediate interview. This time the teacher had made different connections and asked a pair of pupils at a time to explain diffent situations. Moreover, direct questions concerning the electric circuit and the electric current were asked.

The aim of the final interview was to chart the learning results of the whole teaching experiment. Pair-interviews were used in this phase, with writing tasks, and the connection cards. The goal of pair-interviews was to activate all pupils. While the pairs were being interviewed the rest of the group were answering the writing tasks.

Lessons

To activate pupils’ talk as much as possible the lessons were realised as small group discussions. The role of the teacher was to guide learning and negotiation on the grounds of the teaching model described in section 6.5, act as a chairman, and to encourage all to participate. The talk was activated by connection cards, claim cards, a word-explanation game, a true or false –explanation game, a dollhouse-electrification task, and by the broken pocket lamp problem-solving task .

The working method in a small group was as follows: firstly hypotheses were made with the connection cards; secondly observations were made with real connections; and thirdly the observations were discussed, teacher summarised the observations and emphasised the main subject matter. The hypotheses were arrived at in the small group by negotiation, and everyone had a chance to express his/her opinion. The phase of observation also included negotiation. The observations were also compared to the original hypotheses. So, the working method freely followed the ideas of the hypothetical-deductive learning cycle (4.3.2.2).

The last lesson differed from other lessons because of its concluding nature. The summing up was organised by applied tasks, which were designed on the grounds of the earlier lessons. During the last lesson the small group was divided into pairs that solved two problem-tasks: the dollhouse-electrification and the problem of a broken pocket lamp (see section 6.6 and Appendix 3: Problem-tasks for the last lesson ).

Pedagogical conclusion of the design solution

According to needs assessment presented in section 6.1 the pedagogical solutions require some elements to be useful for learning. In this design solution we used games, plays and applied problem tasks to put into practice the requirement for contextuality and the children’s world (B1).The connection cards and other charting ways were used to activate the children’s thinking (A2) and make it possible to work with inexpensive equipment

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(B2). The prolific concrete experimental tasks with hypotheses and negotiations activated practical work (A1), activated work and study, and gave experiences of the physical phenomena (B3). Moreover the pupil-centred small group working activated pupils in their practical work, thinking, and generally in their work and study (A1, A2, A3).

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7 Results 2: Development of external representations of