I need an ensemble piece for my GCSE Music - and the performance date is the 21st April, so I really need to start it now! My school teacher recommended me Diabelli's
Jugendfreuden, for 5 notes (
here), but I think it is way too easy. It only uses 5 notes in the primo, with virtually no complex rhythms and it is in C major.

I don't have any duet books at home, and my teacher doesn't seem to have any of the right standard.
Ideally, I want it to be at the lowest grade/level while still getting full difficulty marks. Around Grade 4-5, I guess. Could you recommend me some pieces? Something I can learn quite quickly and would be suitable for the GCSE? Some specific books I can get would be helpful. Thanks.