Students taking a philosophy class for the first time will find the material on basic concepts in logic and argumentation, and fallacies of reasoning, very useful. The basic concepts in logic and argumentation can be found in course #1

This course is quite large, actually. It contains the introductory material on logic and argumentation (Part 1) and informal fallacies of reasoning (Part 4), plus a full introduction to basic concepts in formal logic (Part 2) and formal fallacies of reasoning (Part 3).

So if you're not all that interested in formal logic, you can just do Part 1 and Part 4. This is a good introduction if you're coming to this for the first time.

However, if you want (or need) to deepen your understanding of the nature of deductive reasoning and fallacies of deductive reasoning, Parts 2 and 3 will be helpful.

If you want to learn more about the value and importance of critical thinking, you should look at video course #1:

This material will help to clear up common misconceptions about critical thinking, and drive home the fact that critical thinking is a multidisciplinary practice that combines both cognitive and performative skill development.