[eaturcheese]

Sounds like a real challenge!

There's plenty you can do with a chalkboard and writing paper. Just look at the whiteboard activity thread for those ideas. Some games that come to mind are:

Scattegories: Write a list of categories on the board (fruit, people, places, animals, verbs, etc.) and pick one letter. Students have to come up with words in those categories that start with that letter. They get points for words that no one else has.
Pictionary
Hangman
Mad Libs
Relay games: The conversation goes down a row like a game of Telephone (Where are you from? I'm from India.) and students write something on the board or snatch something to win that relay heat.
One line story: Give the students a starting sentence (It was a rainy day in Mumbai.) One student comes up with the next sentence, and it goes around the class (or group). Groups can present their story to the whole class.

I imagine roleplays like a shopkeeper and customers would be taboo free unless your students have dirty minds.