The German 50 pfennig coin was issued between the end of the First World War and the beginning of severe hyperinflation in 1922.
The motto on the other side of the coin reads ” Sich regen bringt Segen”. It means “Moving yourself brings blessings”.
However, a more appropriate translation might be “Hard work brings its own reward”. This is an old German proverb, and was commonly used as a motto by the Weimar Republic.