I knew one kid who scored in the 30's. Oddly enough, he wasn't really that great of a student. I don't think he was even in the top 50 of our class (IIRC, he did score 35 or something like that on English whereas that was my lowest score). There were 3 27's in the top 10 of our class & none that were higher.
Good test taker. I am a weird person who thinks that taking tests are fun... I like to read the question, the stems - I like the task of finding out which answer is different than the others. It isn't always knowing the answer but finding out which is different. I have always been better at taking tests than doing other day to day tasks when it gets tedious sometimes. That is good, because when I have been fed up with studying, I have been able to tell myself to just go to bed - because I do better being well rested and just enjoying the task of "taking the test" and getting lost in it rather than stressing out about cramming for it. Those are the people who end up blowing the ACT out of the water sometimes. LOL
Some of those people are just good test takers. It isn't the knowledge in the test, it is the knowledge of the practice of taking the test.