I know there Großer Feldberg im Taunus, Mount Feldberg, at 879m the highest of the Taunus mountains, is a magnet for locals who flock to the ski slopes, toboggan runs and Nordic skiing routes in winter. The summit is home to a mountain rescue service, an observatory and a weather station. The snowiest month is January but conditions in December and February are normally also good. Special buses run between Frankfurt and Feldberg during the ski season.
When it comes to Alpine skiing in Germany or snowboarding in Germany, your best bet will be the many ski areas that dot the Bavarian Alps. Out of all the resorts though, the most popular is Garmisch-Partenkirchen. With picturesque mountains dominating the view, Garmisch features the highest peak in Germany--Zugspitze.
Hope my answer has been helfpul!
Try using the "build your trip" flight comparsion tool here:
Airlines to Germany it will
search multiple websites and get you the best price.
Links of interest:
Frankfurt Germany Skiing and Snowboarding in Germany The Bavarian Alps