Here's a common essay structure I've picked up on, from many sources(From Eliezer Yudkowsky's rationality articles to John Oliver's Last Week Tonight)

1. Introduce a problem/concept - can be a social issue, bias, or a useful cognitive tool.

2. Define/explain what it is.

3. Give several examples or studies.

4. Call to action - propose a solution, debiasing, or a practical real life application.

Also add an intro that grabs attention and promises value.

This seems to work well and I like it a lot, it gives me a pretty universal way to write on many subjects.