Is manjuana an upper or downer?

"Shrooms", psychoactive mushrooms which contain psilocybin and related substances, are a hallucinogen (also known as psychedelics, and several other names), a class which is distinct from uppers (stimulants) and downers (depressants). So the answer is neither. Of course, an individual may feel energetic or lethargic while under the influence of mushrooms.