Incidentally, I don't think I would have encouraged DS and DD to skip GT Chemistry and GT Physics if the three most accepted AP science courses weren't double periods. Their schedule only allows 8 courses and with their magnet program and instrumental music class on top of the standard English, math, social studies and foreign language, there is just enough room for one double period science each year.
Regarding calculus, I think the reasons students take AB follow by BC is because here the prior math sequences are watered down and because mostly juniors take AB, followed by BC their senior year. In my day, Pre-Calculus was one semester junior year and Calculus AB was the second semester junior year while Calculus BC was senior year. In my kids' district, college-bound students must take four years of high school math in high school. Kids like DS (finishing Calculus BC sophomore year)and DD (finishing Calculus BC junior year) will end up taking one or two math courses at a local college.
