<p>IB is standardized/regimented (audited)… much more so than AP (especially when compared against full-IB dilploma requirements). But there are variations from school to school.</p>
<p>At our hs, it was not possible to take an IB class unless headed toward the full diploma (except where there were some combo IB/AP classes). Another hs down the road allows students to pick/choose IB courses, like AP. At our HS, all SL classes are done as 1 year courses and HL as 2 year sequences. Per my CC reading, that can vary too.</p>