Over the last few months, since I began my placement, I have had the opportunity to watch many, many lessons, and I have even taught part or all of some. I have learnt many things about the art of teaching; the amount of work it takes to plan a well thought-out lesson, how to encourage and challenge students, but also how to please your colleagues when it’s your turn to do cake club.
However, I learned the most when I had to stand at the front and lead. In order to teach something you must truly understand it yourself. Osmosis was the topic I was given first, it is one of the more demanding areas of the AS course. When preparing for the lesson, I realised that my long neglected A level knowledge was not up to standard, and I had not been confronted with the topic in depth during my university studies. However, having to relearn the topic was advantageous as I was able, before the lesson, to predict and understand misconceptions which students may have and identify areas which they may find difficult. This meant I was able to address them in the lesson before mistakes were made and to improve the learning outcome. In future, I will take this approach forward.
I have also learned through my observations that it is much better to lead students to answers rather than spoon feed them. However, in practice, student-led learning is much more difficult to achieve. For example, when I planned a lesson on evidence for DNA replication, I gave students selected background information on the famous Meselson and Stahl experiment which had proved the semi-conservative nature of DNA replication. Using existing knowledge of students about DNA replication, I asked them to work out the outcome of the experiment. Such a trial-and-error approach often means that, when students eventually get to the right answer, they are more likely to have understood and be able to retain the knowledge. I then presented them with a full and rounded explanation, so they could correct and understand potential misconceptions they may have had along the way. Learning through such active problem solving strategies trains the students in an important skill that will be useful when they have to perform in synoptic examinations, particularly in this A/B grade topic area where many of the questions tend to be challenging. However, incorporating this important inquisitive teaching style into lessons is time consuming and, in the daily school routine it takes therefore less of a priority compared to covering the content. It was a very satisfying experience that I made the effort and took the time to prepare this lesson in this way, and I got the strong impression that students gained a good understanding of this demanding topic.
In this class on DNA replication, I was also able to incorporate some creative activities, for example students modelled the outcome of the Meselson and Stahl experiment using plasticine. It allowed the students to make mistakes and to do something different than writing out notes – which is often the focus at A level. I also learned the value of having a well prepared worksheet, with the help of which the students could record and consolidate their findings after modelling the experiment. It allowed the students to work independently, which seemed to promote the problem solving approach and enabled me to focus on struggling students to provide one on one help. Although such resources take time to produce, they enable the pupils to get more out of the lesson and hopefully leave memorable impressions. Furthermore, I was able to provide an extension activity where the students attempted to demonstrate the outcome of the experiment, if dispersive or conservative replication had occurred. This provided an element of differentiation to stretch the best students.
The most difficult thing I found in these situations, was explaining a concept which I found obvious but was completely novel to students. Examples in this case were experimental procedures such as growing bacteria in a medium for several generations or the use and function of a centrifuge, which were aspects that I had experienced and done myself. Only afterwards did I realise that I had failed to provide comprehensive explanations for these aspects which were new to the students. It is in this area where I feel strongest that I need to improve through critical analysis of the lesson before I put it in practice.
During my placement, I also learned some unusual lessons, such as the importance of knowing your lesson contents well and the spirit of improvisation. One Friday, the class was doing a straightforward practical to demonstrate the effect of changing the concentration of a chemical substrate in an enzymatic reaction. Students were placing pieces of potato into differing concentrations of hydrogen peroxide and measuring the oxygen produced by the catalase-mediated enzymatic reaction – when suddenly the lights went out due to a power cut which left the laboratory without lighting and electrical equipment. There was some disruption for a short while, but the students were instructed to continue, and they did so; both the practical and the lesson were completed. Key to this success was that the teacher knew the lesson content and theory very well, and could continue to teach through improvising in the absence of any technology. Relying on technology is tempting, but I learned that I need to be prepared to cope without it at all times! There are many obstacles when teaching, but this was not one which I anticipated – but an important lesson to remember for the future!