[Firebird]

Living on a teachers pay is easy, even if you are inside Tokyo, if you are a bit carefull. If you dont mind sharing your Shower and kitchen, why not move in a guesthouse (if you stay in the city). I had a very good chance to speak Japanese and interact with Japanese everyday because they lived with me.

I think what people mean with: If you teach you cant get the culture.
Thats about people who go there for the money, dont speak any japanese and always hang out with their fellow teachers in Roppongi.
If you want to, you can experience the culture.

Like somebody said before, you can get other jobs ( i had 2 other jobs) but you will have a very hard time surviving with that money. I lived inside Tokyo and spend around 4500yen a day. That includes food, accomodation and commuting. Here and there some fun or a t-shirt.