A few weeks ago I did a lesson on German Schlager, but what a lot of people don't know is that, back in the 50s and 60s, most big American (Amis) and British (Tommys) pop stars also had versions of their hits that they sung in German for their German-speaking fans. Nowadays, of course, it is hip to sing or listen to music in English and most young Germans speak it well enough that they can mostly understand the lyrics (though this is not always a good thing. Try teaching your students again and again that the third person in English needs an "s" at the end of the verb in the present simple only to be contradicted by songs where someone sings "She don't call me anymore" or "He sing sad songs all night"....)
Anyway, some of the biggest of the big sung in German at some point in their career and these include:
1. The Beatles
Sie liebt dich, (yeah, yeah, yeah). P.S. What's up with the marching police men at the beginning of the video??
Forget bloated, karate-chopping, Vegas Elvis. Look how adorable he was when he was young! He sings this German folk song partly in German, partly in English and was undoubtedly popular here since he was stationed in Germany during his army days.
3. Johnny Cash
Yes, the man in black apparently trägt auch Schwarz...
4. David Bowie
In the 80s, when there was a wall around Mitte and Prenzlauerberg and Kreuzberg was still full of commune-living left-wing radicals throwing rocks at police cars, Schöneberg was the hip place in Berlin to be. The neighborhood was also home to both David Bowie and Iggy Pop for a while. Of course, by then it was standard to just sing your hits in English but Bowie did Helden (Heroes) in German because, well, I guess he thought it was cool.
5. Bob Dylan
Ok, so I'm not sure if Bob himself sung in German, but here is a Schlager-esque German version of Blowin' in the Wind. Mega "groovy".