This summer my daughter spend holidays in Frankfurt. We decided to combine the trip with the studying German. On the choice of the school I don't regret, thanks to the SMAPSE for the recommendation.
Daughters liked Sprachcaffe Frankfurt very much, especially noted the rich extracurricular program and not straining the schedule of lessons (classes until 12:00, after lunch - excursions, walks, picnics).
The only nuance: it was not always possible In the afternoon to reach the host family. The tube was not taken, it was discarded. In the evening there were no problems with communication.