I'm a junior in high school, soon to be a senior. Anyway, I took an IQ test and scored 120-ish. But on the SAT I got a 2280/2400, which is 99th percentile, and on my ACT I scored 35/36, again in the 99th percentile. In both cases I didn't take a single study session nor buy any review books like most people do to get really high scores.
So now I wonder, since I can discern three cases:
1. I'm moderately smart for the whole human population, but smarter than all other 16/17 year olds taking the test because they've an IQ lower than 120
2. I've actually only mediocre intelligence but I'm somehow really good at thinking through standardized tests
3. I'm really smart but the Mensa only tests for spatial knowledge and pattern-recognition