As to some of the comments about AFS restricting visits and contact, it is for the student's sake. The whole goal of the program is for cultural exchange and understanding. Students are immersed in a new culture to learn about it, and to share some of their own culture with their host community. Students are screened for their ability to adapt, interpersonal skills, their sense of empathy, educational level, intellectual curiosity, and a lot more. These kids are ambassadors for the USA at a very local level. Host families are chosen for their willingness and ability to bring a total stranger, a child (the kids are 16-18), into their homes and to treat them like their own. The bonds that we make are strong and beautiful. It doesn't mean every child's year will go smoothly. Any parent with teenagers can attest to that! But, we've hosted several AFS students in our home, and everyone of them became our "own" kids! I'm so grateful for the AFS families that hosted my son (Brazil) and daughter (Italy) - and me (Australia) - for our years abroad as teenagers.
If a parent in the US keeps in constant contact with their AFS student while abroad, it can make it harder for the student to adjust. I personally had to deal with parents who called, texted, and/or video chatted every single day for the first several weeks their daughter was overseas. The father kept telling her how much he missed her, and said she should come home with every doubt/funny story his daughter told about her new family/school. If she didn't like some food she tried, he said come home, he'd fix her favorite meals. He would call and tell her how much he missed her. Her mother wanted to know every detail of her day. She got more and more homesick as the contact continued, until she asked her in-country AFS counselor what to do? She didn't want to hurt her parents by asking them to stop calling, but she was having a hard time adjusting. I talked with the family, but they said they didn't realize how much they'd miss her, and insisted they keep the contact up. She was back home within a month. It was so sad.