Most international students are eager to improve their language and understanding of the host culture. In return for time given to them to assist with this they may be willing to help local people to learn their language and culture.
If both parties are happy just to talk you can easily decide on topics to discuss along the way and to decide what level of interruption and correction is helpful. Alternatively use an interesting magazine article as a basis for discussion and highlighting of unfamiliar words and phrases. You can also use the cultural/worldview questions referred to in the section below.
For a student who is keen to understand his/her host culture there is a significant opportunity to explore both surface level and much deeper issues. You can ask each other questions about family life and roles, about the homes and environment you grew up in, about typical foods, sports, and forms of entertainment, how education works in your respective countries and then moving on values and beliefs you hold dear.
St Andrew’s College in Melbourne have produced a questionnaire for understanding world views which can give you a variety of areas to explore and suitable questions which in the case of cultural exchange you can ask each other.