Oh, drama class and choir will be great for you to do if you want to improve but choir yes I get it you are singing but you are learning to control your voice and tone. Drama would help you learn to in general learn how to act or be someone else even though you are on stage its befitting because you using voice work as well.
Google Voice Acting videos too: Hotel Transylvania 2: Behind the Scenes of Voice Acting Matched with Movie | ScreenSlam - YouTube