I still think it's odd to have Calculus broken into two years. This wasn't the way it was done when I was in HS and it's not the way it done at the local one.
It's all in how you break up the material though... We have a years of Pre-Calc. Regular pre-calc leads to AB, H. Pre Calc leads to BC. The H. Pre-Calc includes some beginning Calculus topics to get a jump start on the next year. Kids who go right into BC, don't skip AB. I agree it would be difficult if it's broken up that way.
Why it's strange is because of how the AP tests are given & colleges give credit. One university DS is looking at gives credit for 2 'quarters' of Calc for the AB Calc Test, and 3 for BC Calc. IF you take both tests on different years, you only get credit for the later test. It's also odd since the letter ABC are meant to be break the material into 3. So if you take Calc AB one year, the next year of Cal BC would just be the C part and be slower? Or do they add extra material?
A million years ago when I took Calculus in H.S. we did a looped two year BC course. Same teacher / same kids / same textbook. I don't remember if the division occurred neatly at the boundary between the two we just picked up where we had stopped the previous year. Structurally I think it was very successful. Since BC is a superset of AB its also very easy to split the material up just that way. An AB class could be the common topics/chapters and the BC class the additional ones which is how some of our local high schools do it here.
