Mike Tuke’s

Organising experiments Why do experiments The purpose of experiments is, above all, to help students learn some geology but it is also for students: to see geological processes or simulations of them to make deductions from the data they have collected to learn the experimental skills of observation and measurement to develop skills of evaluating the reliability, accuracy and validity of experiments. Experiments make students think and thus are an effective way of learning, much more so than chalk and talk. They add variety to lessons. Discussion is a very effective way of learning and experiments are, in my experience, the most effective way to encourage discussion in Geology classes, both before on how to carry out the experiment and its geological relevance, and after, in drawing conclusions and evaluating the results.  Experiments can be used to reinforce information given in class or can be used to lead into a topic. Students also generally enjoy doing experiments. General The experiments on this website are designed to be done by pairs of students but many can be done by individual students.  You can either run the experiments as they are simply by photocopying the instruction sheet or, better, you can modify the instructions to suite your own teaching. Any room with enough table or bench space is suitable.   Some experiments use mains electricity and therefore require a power point.  Water is often needed and lab with running water and a sink is certainly convenient but all experiments could be done without this.  Mains gas is never needed. All these experiments have worked well for my students but it would be a wise precaution to try them out yourself before inflicting them on your own students. Before the experiment It is generally a good idea to discuss the experiment with students before they start it, to enlarge upon its purpose and to think about its geological relevance, what are the variables and what aspects are controlled, what needs to be recorded and how, how the experiment relates to what is being taught in lectures and any safety aspects.  Encouraging students to devise an experiment to solve a particular problem is an effective way of keeping them interested and making them think. They can then, after discussion, do an appropriate experiment from this website.  They can then evaluate the pros and cons of their own method and the one given here. Students should sometimes be asked to write hypotheses.  If they do there should always be a rationale for their hypothesis otherwise it is just a guess. After the experiment At the end of every experiment students should be able to draw a conclusion or make a statement about the results. Class discussion of the results and evaluation of the accuracy, reliability and validity of the experiment is also productive. It is not always necessary for students to write a full formal report. Depending on the circumstances you may wish the students: 1. Just to write down their conclusions 2. To write down the purpose, relevance and conclusions with or without evaluation 3. To do a full formal report. A list of topics which students should address for a full report is given below. 4. Slavishly copying out the method is not usually a good use of student time. Getting students to answer questions which use the results is a very successful way of ensuring they learn from the experiment. Safety There are no significant hazards with any of these experiments.  I have not had any injuries in my class yet (touch wood) in spite of teaching Geology for 37 years and having spent nearly half of every lesson doing practical activities.  However students should be aware of the dangers of boiling water, heavy rocks rolling off tables, blown sand and the danger of shock if electrical apparatus is not handled properly especially in the presence of water. The Headings Each experiment has several headings.  These are explained below. Purpose This is a simple statement to inform the student why they are doing the experiment and what they should find out from it. It is very important that the student understands the purpose of the experiment and how it relates to the theory being taught in class. Activities In some experiments there is only one activity whereas in others there are several related activities. It is not necessary for every student to do all the activities for a given experiment.  Pairs of students can each do one activity and then report back their results to the class. Alternatively just one of the activities can be chosen, usually the first is the best if only one is to be done. Instructions Each activity has its own set of instructions.  Where the instructions for the second activity are very similar to the first then only abbreviated instructions are given to save space.  Teachers may want to write out these in full so that there is an appropriate set of instructions beside each piece of apparatus. This is particularly important if students are not all doing the activities in order. The sheets give instructions for doing the experiments but not on how it should be written up. Questions Asking questions at the end of an experiment is a good way of showing students how the information gained from the experiment can be used and of reinforcing that information in the student’s memories.

Earth Science Activities and Demonstrations