While a foreign exchange student is expected to know your language, she may not be familiar with the normal every day phrases you use. It can be frustrating for both you and her if you have to repeat yourself a lot. She may also have a strong accent, which may be difficult for you to understand. Speak slowly at first and be patient. Make the effort to teach her more words, so she will be comfortable going to school with other students.
Foreign exchange students travel to different countries, where they do not know anyone. They are away from their families for months and they may not be able to relate to anyone in their new environment. While it is certainly not easy for the student, it can also be pretty difficult for the host family to know that their foreign exchange student is homesick. Always ask him how he is feeling and if there is anything you can do to make his experience more comfortable. Also, let him make phone calls or use your computer to contact his family when needed.
It is possible that your foreign exchange student may not get along with one of your family members. They may have a minor disagreement or they can strongly dislike each other. This can pose a problem because you all have to live together in the same house. Sit them both down in a quiet room and ask them about their differences. Try to come up with solutions to the problems, so living together will be more peaceful.
Since you will have an extra person living in your home, your monthly expenses may go up. You will have to purchase more food and your utilities will cost more. Also, your foreign exchange student will want to call her parents occasionally and international calls can get very pricey. An Internet telephone or country specific calling cards may be good investments. Before you host a foreign exchange student, make sure that you have enough money in your budget to support her. It is not fair to student if you can't afford to take care of her basic needs.