How teachers help learners to make sense of concepts

In their interviews the teachers indicated that they used different types of strategies in order to help learners make sense of concepts on the topic on transpiration. Below are the strategies that they highlighted.

Use of local materials

When asked about how they helped learners make sense of concepts on the topic on

transpiration, it came out clearly that both teachers made use of locally available materials to demonstrate transpiration. Teacher 1 said the following:

…you can even come up with a potometer is one example to demonstrate transpiration to see how plants up-take water and again it shows you how the plants lose water. I think you can just take a plant, although it is not a potometer. You can just take a branch of a tree, then you put it in water, then you cover it with plastic again…you can simply use an open can, then we

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put pure water, and take a branch of a plant, that I prefer to use to measure the rate of

transpiration…just any type of material that can be found in the environment instead of using potometer”. (Appendix C, I-T1: 37, 49).

Teacher 2 indicated that he made use of locally available material to demonstrate transpiration, and he noted that: “…sometimes I have to improvise to make my own

Potometers by using the available material and then, this in all it will convince learners and then they will believe that it is real plants normally lose water through their leaves”.

(Appendix C, I-T2: 19)

Something I found interesting was that both teachers said they made use of locally available materials, which was also observed in class, where teachers had to guide learners in setting up experiments using local material (See appendix B, O-T1: 1 and O-T2: 8).

Use of analogies

From the interview, it emerged that Teacher 1 uses analogies to describe concepts. She said that: “They can understand if you describe concepts at the beginning of the lesson….you can even ask them to run, they start sweating, then you explain to them that, same applies to plants, but for plants it’s not because they exercise or they run, but because of higher temperature”. (Appendix C, I-T1: 17, 21).

There is a possibility that this teacher confused some learners as the analogy implies that higher temperature causes the plant to transpire. The teacher could have clarified that higher temperature causes the plant guard cells which control the stoma where water is released to the atmosphere to open, while colder temperature causes the openings to close. When stomata are open, there is an increased rate of transpiration.

Although Teacher 2 did not comment on the use of analogies during the interview, in the lessons I observed, he used analogies to help learners make sense of concepts, where he explained how temperature and wind affect the rate of transpiration using an example of washing clothes (See appendix D, O-T2: 124).

Considering prior knowledge

Teacher 2 highlighted that he helped learners make sense of concepts by introducing a lesson by relating to what learners already know. He said that:

About transpiration this topic is a… almost common in all natural science subject especially learners they normally meet this subject this topic either in Agriculture, or in Life science back to lower grades and even now in Biology. For me to introduce this topic to them, they normally consider the parts of the plant that are involved in the absorption of water, either

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from the soil, and the other parts like the leaves that normally let water move out of the plant.

By looking at their functions of those parts and then as a result (Appendix D, I-T2: 10).

Although Teacher 1 did not highlight that she considered learners’ prior knowledge when teaching, in one of the lessons I observed, she asked learners to define transpiration before giving them the correct definition (See Appendix D, O-T1: 12).

Guidance on practical work

Teacher 2 indicated that he guides learners on how to set up and use equipment for practical work. He pointed out that:

But before learners use that Potometer I have selected out of other Potometers, it is me who has to...aa…make rehearsals for the learners aa… that, first of all, the Potometer it is used like this, like this part of...like if I have to be specific for example, aa...when you are setting Potometer, we have to make sure that there is no air in the Potometer, aa…that is why the Potometer is normally set under water, aa… to avoid bubbles. Because some of those bubbles may interfere with the experiment and you may not able to see or to get the results that you want to get (See appendix C, I-T2: 51).

Teacher 1 did not mention that she guides learners on practical work to help learners

understand concepts but it came up in the interview when she was asked how she ensured that when the class worked on drawings, girls also get a chance to draw. She said:

It starts with when you make it that individual can come up with this, and it should be done under supervision, otherwise if it is not done under supervision of the teacher again, they can ignore fixing the part and come up with the model. And, but if you do that and you make it an issue for each and everybody, under your supervision, I hope next time they would like to involve or to take part in such project (Appendix C, I-T1: 130).

Questions and answer strategy

In an interview, Teacher 2 affirmed the use of questions and answer as a strategy to help learners understand concepts of transpiration. He said the following:

Sometimes or immediately after the lesson, I also, ask questions, oral questions, aa…and then apart from oral questions I also set questions basing on potometers, just to see whether learners have understood or they did not. And then, I also…set some very short questions, in other words I also set test s that are related to potometer and then that test it has to be given to learners. Then, as a result, I am testing their knowledge. Whether they have understood the

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function of a potometer, whether they have understood what transpiration is all about or what is that causing transpiration in plants and how can transpiration be stopped. In all those things I asked through oral questions, through class activities, and through test (Appendix C, I-T2:

67).

Teacher 1 did not mention that she uses the question and answer strategy to help learners understand concepts, although it transpired in her observed lessons. For instance, at the beginning of the lesson, she asked learners to define transpiration (See appendix C, O-T1:

16). In addition, she asked learners to explain how light intensity affects the rate of transpiration (Appendix C, O-T1: 166).

After having looked at how teachers help learners make sense of concepts on the topic on transpiration, the next section presents data on the challenges teachers face.