This article from the Writing Center at the University of North Carolina explains what argument is in academic writing, why you need it, and how to go about it. It covers making claims, providing evidence for your claims, and using counter-argument. There is also a very helpful section on critical reading. It talks about techniques to help you see the arguments that other authors are making instead of taking what they say as statements of fact. This helps in critically evaluating the evidence they present and helps you learn techniques for making effective arguments yourself.