Scholarships are a form of financial support which does not need to be paid back. Excellent academic results are usually a requirement but sometimes other factors are important such as political or social involvement. They are offered by organizations such as political parties, churches, the state, industry or private foundations which all have their own goals. The better the student matches these goals, the higher the chance of receiving a scholarship. For some organizations you can apply yourself directly, for others you must be recommended. More information on scholarships suitable for international students can be found here.
A list of all large German Scholarship Foundations and other useful information regarding scholarships can be found on FELIX here. (Login with your FELIX password.) In line three under "Zielgruppen" you can see whether the respective scholarship is also available for international students.
Here is a selection of some of the scholarships available:
Studienstiftung des deutschen Volkes
Stiftung der Deutschen Wirtschaft
Evangelisches Studienwerk Villigst
Ernst Ludwig Ehrlich Studienwerk
Südweststipendium des Verbandes Südwestmetall
Stiftung Begabtenförderung berufliche Bildung
HFU-Stipendium "Auslandsstudium mit Kind"