Golden Teacher (short form GT Mushroom) is a popular cultivated strain of Psilocybe cubensis, one of the world’s best-known hallucinogenic mushrooms. The name reflects the light brown, yellowish, gold top caps of this strain (wild P. cubensis is usually a little darker) and also the insight many users report receiving.
Whether Golden Teacher is really more educational than other varieties is unclear; many users swear that the quality of the trip depends on the strain of mushroom involved, with some being more visual, others more physical, and so on, while others insist a cube is a cube is a cube (potency does vary). Either way, P. cubensis is known for producing a variety of enjoyable “symptoms,” including euphoria, introspection, and hallucinations—and some that are less-pleasant, such as nausea and sometimes  anxiety. Serious side effects are rare but possible. 
 
*Psychedelics please medicate with caution*