i'm thinking about starting a local yoga class next week, purely because i am SO BORED! though, i don't really know much about yoga. is it hard? do i have to put my legs behind my ears?
No it's not hard - check it is a beginners class though!
I used to do it and mostly it was about improving posture, strengthening your back and increasing (gradually) your flexiblity, and we were always offered a choice of 2 or more difficulty levels depending on what you could do.
It would depend on what poses you choose to practice. Some poses are hard or even very hard to do, while many others are so easy to do that you could do them at the first try.