Bluuuuuuuuuuuuue. Honestly, that's the fist thing that came to mind. Personally I'm not a fan of monochromatic themes to be honest, but they do work for some people. Yours is a little hard on the eyes, some of the black text is hard to read (for example, the notes and asks). The issue with monochromatic is that nothing stands out, there's nothing that specifically pops out unless one of the admins answers a question with a gif.
Plot
I've definitely seen plots like this one before, quite a few if we're being honest. I enjoy how you incorporated some humor to it instead of just having paragraphs of cut and dry plot information. The issue is that it doesn't really flow together. I would mention in the first paragraph that it's in Newport Beach or by it. Without that connection earlier, the second and third paragraphs could honestly read as two separate plots.
Having a page that explains the places of the school keeps everything consistent. I've always been one of those people who involved too much detail that isn't relevant but you guys don't do that while still providing information that isn't completely central to the plot. It keeps your view of the school and the members relatively the same.
I would advise you to add some more information to the sidebar plot. Yes, the lyrics are fun and nifty but sidebars should really be used to draw members in at first glance. I know you have the "read more", but I would just put a little bit more into the sidebar.
Rules
First off, your rules are really long. You could condense a lot of them so it doesn't look like a long list to new members. Create a section about OOC behavior where you talk about both how OOC should not be on the IC dash AND how OOC drama won't be tolerated for example. All of your rules make sense so I'm not saying you need to take them out, but it would be easier if you combined some.
I'm a little confused about the comments with exploring the character and then keeping it to the character bio. Really, it depends on the level. I would be more specific with what exactly you're looking for in terms of having freedom with the character and keeping it as written.
Characters
Your bios are not always consistent. Some of them are much longer than others and include much more information. I'm assuming the discrepancy is between characters made by the admins and that made by the player.
I would branch out to having Freshman and Seniors as well. What good comes from not having those characters? If you don't want them part of the RP that's fine, but don't give that option then.
The tweets are a good idea. They allow more insight into the character without specifically saying it. However, the issue is that some of them don't really provide much light. "back in town" shows that they aren't an insider but that can easily be said somewhere in the bio.
It's a personal preference, but if you're going to have a relationship section, everyone should have something. It doesn't have to be a relationship, but it could easily be friends, enemies, ect. You obviously don't want everything spelled out, but it gives players some direction and a connection right off the bat.
Other Comments
You guys are friendly towards members. I honestly don't have much to say here.
Overall Thoughts
You guys have a good RP for those who like high school boarding schools. I would recommend spicing your theme up a little bit by adding a pop of one other color and work on creating a connection for all of your characters.