The author uses ethos (author credibility and trust in their credentials) by using the word "our" so often. This places the author in collaboration with the reader, showing that he believes that they are all one and working together to achieve a common purpose.
<span>an attempt to explain an origin</span>
The fallacy being use here is when they say "we should all wear our school sweatshirts on to create sense of unity because they will help them feel like a of the school" the should already feel of the school because they are going to that school that's how I know this is a fallacy