"To graduate a class" means to formally complete and pass the requirements of a specific group of students who have finished their studies, enabling them to receive their diplomas or degrees. Full definition
Figure A shows the rates of immediate college enrollment in the first fall after high school graduation for the high school graduating class of 2013. (nscresearchcenter.org)
I teach graduate classes at two different state universities and know this saying to be true, first - hand. (biggerpockets.com)
Now I teach college and graduate classes from time to time. (huffingtonpost.com)