As an adult learner, you may be in a position to do a little research. I recommend a little self-help on this one. Suggestions you get from this posting might ALSO be useful. I do not intend these remarks in any spirit of criticism.
But sometimes I think we can all be too passive. I see this on the Piano Forum all the time. Students are asking for what they could easily do themselves.
Look through displays of sheet music at the music store. Research your favorite composer's piano output. Consider some graded books other than what your teacher recommends. The Bastien Christmas books are great-- and some are very easy!
As to follow up my point of students being very passive and too easily led, how about the people who keep writing to the forum asking that the difficulty of a group of pieces be ranked?
Really, if people have been playing for some time, can't they just page through the music and figure out how hard it is? If someone were to give me three pieces, I could look through the music and tell you very readily what pieces would be easy or hard FOR ME. Or do I have some miraculous ability some people lack?
To answer your question more specifically -- For a couple of easy classical pieces you could consider at your level, consider the John W. Schaum arrangement of Pachelbel's Canon [actually transcribed into "C"], or Ravel's 1913 "Prelude," which is available on the internet and is only one page long. Satie also has some very easy pieces, including the triptych of children's pieces for "Ko-Kou."
Topic: repertoir grade 3- adult beginner