Midas and Pactolo are rival rappers. At a show, Midas comes down with a cold and cannot carry on singing. This leaves his rival to take all the glory. He wishes that it was he who was famous. However, things don't turn out as Midas planned and soon everything he touches turns to gold - in a negative way.
Could be used to create a song or a rap in German - perhaps about the Midas plot. Take the melody from a well-known children's song, perhaps 'Brother John' and ask the children to write simple lyrics for it about Midas. For a rap song you might want to look at rhyming words, eg 'Preis - heiß', 'Fluch - Buch', 'Gold - gewollt'. Ask the children to come up with a few rap lines and perform them in front of the class. Perhaps stage a competition and let the pupils vote for the best MC!
Fortune cookie game: hand out little strips of paper and ask the children to write fortune cookie wisdoms or prophecies in German. Start off with a funny, if not slightly silly example to set the tone, eg. 'Gold und Glück und Gaga beginnen mit G. '