[quote=@KatherinWinter]
[@DarkwolfX37] Those are good suggestions. I like the idea of this being a required class for new arrivals. The only problem is that it doesn't explain the second year students. I suppose they could be there to help guide the first years. I don't want to do complete cannon but I do want to follow the idea of the soul eater.
[/quote]

I could see participating in this class as an easy half credit elective for second years, to give assistance when needed or even as a test for their ability to lead. 
Or it could be a test for the second years to try to hide themselves and pass themselves off as first years as an assignment related to covert operations, as sort of a "introductory to covert ops," or more likely a "practicality of covert ops" (since introduction wouldn't really make sense to just thrust the students into a test that would take anywhere from a day to an entire semester) class' test. Like they're graded on how well they integrate and how long it takes for them to be outed as second years, meaning they'd have to be careful outside of class too. I can imagine Sid giving something like that as an assignment worth 10% of their final grade or something. 
And then the first years would be told during another class, "introduction to covert ops" would fit well here instead, that there are second years disguised among them in one of their classes but not told which class, and 10% of their final grade relied on their ability to learn which students are second years without letting other first years know. A sort of "if you take too long then you fail because you might have just been told the answers unless you discover someone who hadn't been discovered yet" thing. 
It's convoluted, but I could totally see it happening. Then the second years would just choose the class they already are a part of. 

I could probably come up with other reasons for second years being there, given enough time.