They say there's a very strong link between scent and memory, which makes this a perfect solution for the studious!
Set up in the common room with a spare bit of parchment and let the smells of lavender, peppermint, and fresh cotton stimulate your senses into memorizing that pesky potions essay. As we all know, your housemates may be more creative than studious but not to worry! The creative will love this clean, fresh scent just as much.
Don't worry about the other houses' insults to your supposed snobbery, you know full well that you have the best smelling common room in the castle.