Research Design
This section should explain exactly what you did, how you did it, and with whom you did it - e.g. access, type of school, how many in your sample, how many visits etc.
Access: Researchers need to bear in mind not only the practicability of the chosen sample - but also whether the sample can be accessed. Gaining access to Year 6 pupils, for instance, could pose all kinds of difficulties. If it is planned to carry out interviews, issues are raised regarding parental permission, school co-operation, local authority involvement, etc. If it is intended to use questionnaires to gather data, not only does the researcher need to consider the practical matters of distribution and collection - but also the more fundamental issue of whether the questions will be properly understood, interpreted and answered by the target sample.
Sample: Sampling is the process of selecting units (e.g., people, organizations) from a population of interest so that by studying the sample we may fairly generalize our results back to the population from which they were chosen. The sample is the group of people who you select to be in your study. Notice that I did not say that the sample was the group of people who are actually in your study. You may not be able to contact or recruit all of the people you actually sample, or some could drop out over the course of the study. The group that actually completes your study is a subsample of the sample -- it does not include non-respondents or dropouts. In your study you should clearly explain the criteria used in selecting your sample.
At undergraduate level the most common forms of sampling include:
Convenience sampling
The researcher simply chooses respondents from those closest to hand until the sample size has been obtained. Also known as accidental or opportunity sampling.
Purposive sampling
Researchers hand pick the members to be included in the sample on the basis of their typicality or specific characteristics.
Snowball sampling
The researcher identifies a small number of respondents who possess a specific set of characteristics of interest. The researcher then uses information provided by these respondents to get in touch with others who also possess the characteristics set. This can be particularly useful for sampling a population where access is difficult - or who may not readily be identified by more conventional means (for example, gang members or drug addicts).
If you want to understand teaching strategies in the classroom, you will ask teachers not parents, so this is a purposive sample.
Click here for some additional information on sampling: Sampling Information