I have a Germany resident permit that's valid for the time I back to Germany, am I an EU resident?
A residence permit is a prima facie evidence of residency. However, it is granted on specific grounds. If you are not coming back after your US stay to study in Germany, your entry may be scrutinized.
A German residence permit also expires if the holder was ...
No, a return ticket is not required, but other restrictions may apply.
For a tourist or temporary visitor, without a return ticket, border guards will doubt if you actually plan to leave the Schengen area after your authorized stay and can refuse entry if they are not satisfied that your plan is genuine.
No visa is required
But this does not apply when your ...
No, it is not common.
It may be possible for some people to work their way around Europe by teaching, but most people who want teachers for their kids want someone who is around long term. Someone they can check out before the start of the work and someone they can rely on to be there for a whole school year.
It might be possible in couch surfing, via the ...