Different professors will have different standards for how to handle GAIT use in their classroom. Some will not allow any use, in which case, there is not a way to use them ethically for that course. When they are allowed, ethical academic use requires citations and transparent documentation of exactly how it was used. Consider keeping copies of the transcripts in case your professor wants to see them as well.
GAITs require significant resources to run. This includes water to cool the servers and many rare metals and minerals. The water use contributes to drought, and the mining for the metals and minerals damages the environment. Additionally, the power use needed to run the GAIT servers is astronomical. These are just a few of the environmental concerns exacerbated by GAIT use.