General course requirements
One very important thing to consider is schools’ policies regarding the completion of prerequisite courses. Most schools require you to have completed or have signed up for all prerequisite courses at the time of application. A few schools, like Harvard and Columbia in 2014, required students to have completed their course requirements only before matriculation, meaning that candidates were allowed to apply without having registered for or completed all of the prerequisites. However, at Harvard, the admissions committee states that most successful applicants completed most of the required courses prior to application, and at Columbia, the number of incomplete prerequisite courses at the time of application is limited to one or two].
There are several prerequisites common to many schools. These include biology, organic chemistry, inorganic chemistry and physics which are required at almost all schools. English, college mathematics and humanities are also common requirements. It is a good idea to look at prerequisites for the school you want to apply to early as some of them require quite a few courses that many students may not normally take. For example, in previous years Johns Hopkins has required 24 credit hours of humanities or social and behavioural sciences.
AP and IB credit
Some schools allow you to use AP credits to satisfy prerequisites if certain conditions are met. For example, universities like Penn State require you to have received earned credit toward your degree for the AP courses from your undergraduate institution, while some universities like Harvard require only that the credits allowed you to take upper level courses at your university. Several schools including Loma Linda, the University of Nebraska and many other schools either don’t accept AP credit toward prerequisite courses or strongly recommend that all AP credit be supplemented with higher level subjects. It is important that you double check the policies from the admissions offices or the schools’ website for the programmes you wish to apply to.
Several of the schools that accept AP credit still set strict limitations on how much AP credit you can use and what subjects you can use it for. For example in 2014, Harvard allowed AP credits to be used to meet one semester equivalent of the chemistry requirement.Another example is Cornell Medical School, which only allows students to use AP credit toward the physics requirement. If a student has AP credit in any other area, they fulfil the requirement by completing advanced science coursework.
If you have received credit for prerequisites, you need to check the policies regarding AP credit for the schools you wish to apply to. Doing this early in your undergraduate degree will allow you to take any additional courses you need to take.