If your not looking for the one night stand or don't want to take such a brazen approach just take out the "watashi no uchi de" part.
"Nihongo wo oshiete kurenai?"
Will you teach me Japanese.
Actually I think this works even better because with this phrase you won't scare off a lot of potential cuties.
Once you got them as a friend its up to you what happens next.
My girlfriend told me a funny one. Say "Karaoke ni iku? Hoteru de "
Want to go to Karaoke? In a hotel....
I guesse a lot of guys use that. It just depends on the situation. Like I've been preaching, get the Japanese girlfriend and your language proficiency will skyrocket. After that you can start making up your own lines on the spot. Don't forget the run that "strong machisimo" game, they go nuts over it. Just don't over-use it.
p.s. Instead of watashi which is kinda girly/formal try using Boku. Enjoy the thrill and excitement that is language learning.