College prep is a confusing term because it can refer to three different things!
Sometimes, calling something a college prep class is just a way to differentiate it from remedial classes on the one hand, and honors/AP classes on the other. Other times, college prep is a way of describing a bunch of government or private programs that are designed to increase access to college for those who would ordinarily be unlikely to go. And finally, college prep is a short name for high schools that place an overwhelming emphasis on getting their students into college.
But don’t worry. Whether you want to read about standard high school classes, learn about programs that will make college easier, or are curious about public and private high schools that really stress college admission, you've come to the right place.