The obvious is any textbooks, reading texts, or coursework that you need. I like to organise my ring-binders by subject with different colours; it was a happy coincidence that my Pukka notebook matches. I never used to split my subjects up like this, but believe me, it makes everything so much easier to find!
The other obvious is stationary. Okay, maybe this looks a little excessive, but I use all of these at some point in a week of college, promise! Coloured pens are great for taking notes, or making notes on coursework or books, and highlighters work in the same way. It's handy to coordinate different coloured pens with different subjects etc. as it makes everything easier to differentiate between. And if you don't like writing on books or if you're not allowed to (for example with books borrowed from libraries) then writing on little post-its like the ones above are great - they're small so you don't cover up much when you stick them in a book.
Another thing I find handy to have is notecards. I bought these ones in Waterstones for 99p, but you can find them in many shops - or even better, make your own! I mostly use them for writing out definitions or for quotations I need to use in essays, and I usually colour coordinate these too. They're quite good for testing yourself with and are also really easy to carry about with you; when I have tests or exams I usually pull them out on the train - no more lugging out my massive ring-binder.
And here are my beauty/extra items. If I'm just at college for a couple of hours I don't tend to take a full make up bag with me - just a compact mirror, whatever lip product I'm using at the time, some pressed powder, and this little twist up powder brush which is great for a bag. I pictured two lip balms here because I love them both equally. I also tend to use them for different scenarios, but that's another story for another day. I also have two perfumes included because I'm indecisive. Then there's the essential hair ties and bobby pins just in case, and headphones! I always listen to music while on the train to and from college. Something else I thought worth showing was 4head, which is a roll on headache reliever. I plan to make a blog post on this within the next week but the jist of it is that you rub it on your forehead, it tingles, and your headache is gone. It's so easy to use and perfect to take to college (or anywhere else, really) because it's discrete and you don't have to go through the annoyance of taking pills.
Other things worth mentioning are a purse, mints or gum, and water. Everything above fits into my bag into little pockets. Nothing mentioned here is really that extraordinary, but hopefully you will have picked up some organisational skills. And if that fails, at least you've had a little look into my life.
Do you think there's anything I've missed? Do you have any more tips for me?