I agree.  I think the GRE math section is a joke.  The SAT and ACT math sections, I thought, were somewhat challenging for my middle school son (who took SAT in 7th grade and ACT in 8th grade) because he has only taken a limited number of high school math courses, but he ended up scoring really high.  This made me even more dismayed that the average score of college bound high-school graduates is so low.  It really tells how weak the K-12 math education is.
Same goes for reading, actually.  The dismal national average score of SAT and ACT really has no excuse.
I also agree with someone else earlier in this thread who mentioned the question "why should all kids be college ready?".  I think the society cares too much about a diploma instead of what a person is really capable of doing.  The high school curriculum, in my mind, is so watered-down these days, we are simply sending kids to college to learn a lot of the stuff that they should have learned in high school for free!