I’m currently having an on going freakout about grad school (despite it being at least two years away) and I was looking up info on the GRE, and apparently the math part doesn’t include any calculus questions. So, I could theoretically have taken it right out of high school?
In theory, yes. Almost everyone I asked about the GRE before I took it told me it was little more than a slightly more difficult version of the SAT, and my experience actually taking it largely bore that out. In practice, most schools only accept GRE scores dating later than five years prior to application, and very few people come out of high school thinking “I want to spend the next decade of my life at university!” so it rarely happens.