When planning for a practice-based enquiry or small-scale study you will most often be confronted with the choice between an action research or case study approach. Strictly speaking, there are many approaches to enquiries, but for practical reasons the action research or case study approaches are amongst the most popular for teacher-researchers.
Your decision for one or the other approach must be well justified and to this end you must consult research methodology literature. However, in the following there will be a simplified exploration of the two approaches to get you started.
What is action research?
Action research should be considered as a way of life in the classroom. As a reflective practitioner you will observe what happens in your class and then identify an issue or problem that you need to address. After consulting relevant literature you will then formulate a new approach or intervention, which you carry out in your classroom. Once you have worked with this intervention you will reflect and reconsider its effectiveness and impact and the cycle can start again. For a practice-based enquiry you may go through several cycles or through one cycle only. The advantage of the action research is that it naturally develops from your teaching practice and that it addresses real issues within your classroom. Typical critique of action researches would be that they are not rigorous or systematic enough.
What is case study?
A case study is more difficult to understand because it can be a method as well as a methodology. Here we only look at case studies for their methodological function. If you want to learn more about a specific issue or you want to explore a particular problem or occurrence, then the case study is for you. The description of what makes a “case” differs in various research methodology publications, but generally speaking a “case” can refer to a group of people, a specific person or issue, a collective of ideas. The advantage of a case study is that you get to know the status quo in all its facets and so you gain a deep insight into your field of study. Common critique of the case study approach is that it is so specialised and specific to the context of the research that generalisability is lost. Sometimes it is also said that the mere description of a status quo is not practical for teachers because there are no changes. My argument would be that detailed knowlegde of what happens in your classroom or school can lead to recommendations for future practice. It is just that you do not enter a cyclical approach of evaluating and revisiting your suggested changes.
Action research or case study?
Both approaches have their benefits and limitations within the realm of practice-based enquiries. The choice therefore depends on what it is that you want to find out. Are you planning to introduce a new teaching strategy or changes or interventions with some or all of your pupils? Or are you trying to explore a specific topic? The former would be a justification for action research, whereas the latter hints at a case study. You must be guided by your research focus, your research question or hypothesis and by the research methodology publications you consult.