Once you have explored or been given your topic, gotten one that works, and come up with some content, you need to decide what point you are trying to make. That’s the basis of a thesis statement or claim. It’s the “So what?” of your topic. This “so what” is present in any kind of writing: formal papers, essay question responses, emails, presentations, Twitter posts, proposals to clients. Every piece of writing needs a focus.
In a paper, a thesis tends to be more formal—usually one or two sentences that state the main “so what” of the paper.
For example, let's say your topic is about Native American children being fostered in non-Native homes.
What are you going to say about this topic? This might lead you to think about audience and purpose again. Are you writing to Native American families to discuss a solution to this issue or to explain why it might be happening? Are you writing to the director of a social service organization that places foster children to persuade her to take a new approach to fostering Native American children? Are you trying to show the inequity in foster programs for Native and non-native families to a more general audience?
Once you figure out your audience and purpose, then you can start thinking of your thesis.
So, let’s say your audience is class of graduate students in a social work program at a local university. Your purpose is to inform them about the possible problems with fostering Native American children with non-Native families.
Next, you can go back to your exploring and look for information, examples, evidence, and research that you collected. You might need to go back and look for more now that you really know your focus.