I didn't really have much testing until during middle school, but staring in freshman year I took the PSATs and AP tests. All the PSAT prep we did was vocab in English class, and then in Junior year some brief prep in math. Luckily most of my class sizes were and are small enough that my teachers could give us individual attention if we needed/need it. As a second semester senior, I don't need it anymore. My friends had the FCATs up through 10th grade, after which they changed gears into (P)SAT mode. I'm not sure if their teachers taught for the SATs, or just taught for the class at that point.
I've had teachers that teach for the APs and teachers that teach the class topic, and I'm of the opinion that if a teacher teaches for the class, and not for the test, and does it well, then a byproduct of the class should be good grades on the AP test. I'm also of the opinion that the AP Lit and Lang tests need to be remade, because it is incredibly hard to teach critical reading. Math and science AP tests make sense, because there is a right and wrong, but language is much more subjective.
Testing is important, however. While the SAT isn't perfect, and while I don't think it will ever be perfect, it's a necessary evil. It's a standard--or as close of a standard that we can probably get to, and so we, and colleges, still need it.