I need help identifying a completely unknown plant for my biology class
I'm no expert on plants but it could be a kalanchoe. That's based mainly on the leaf characteristics and size. 



There's some 120 or so species mainly originating from the old world. These are quite drought tolerant as yours seems to be. They are a common houseplant and there are ways to stimulate reflowering so that also makes it a good candidate. 

Image source.