Yes, they are all correct.
The funny part was you/I - sounds a bit strange.
not a teacher

Interested in Language
Hey guys,
Are all sentences correct?
You were always my dream girl.
My dream girl was always you.
Yesterday you were the funny part, not I.
Yesterday the funny part was you, not I.
(Many guys would probably say "not me", but I stick to my "not I")
All sentences with was sound strange but I think they are correct because you is not a subject but a subjective complement.
And please don't focus too much on the I/me
Cheers!
Yes, they are all correct.
The funny part was you/I - sounds a bit strange.
not a teacher
Part is a fraction, section, or constituent of a whole which can be something or someone, but you can describe funny part of something such as a story, movie, or a party. So describing someone using a linking verb (be) sounds odd. You can say:
Yesterday you were the funny part of the party.
Yesterday the funny part of the party was you.