<p>Last year for APUSH, I had a summer assignment which got me prepped for the class (got a 5). Since I started high school I have felt like I am not retaining information as well as I used to during summer vacation, especially in math. Is this normal? This year I will be taking AP U.S. Government and AP Calculus (school offers AB/BC, which I don’t really understand at this point whether it is both in the same year?). There are no summer assignments, so I would kind of like to get a head-start/introduction into the classes. I don’t necessarily want to get any exam review books say from Princeton or Kaplan, which I suppose I will end up getting anyway. But, are there any good introduction books for the classes just to get an idea of the curriculum and start practicing my algebra II and Pre-Calc skills?</p>