My D20, also a STEM kid, took AP English Lang, AP Environmental Science, AP Calculus BC, AP US History and AP Chinese and 2 PLTW classes (biomedical science, and human body systems). I was a very heavy schedule as she was a competitive gymnast and trained all year for 22 hours a week, coached special olympics, and was in 4 clubs. I have already told my younger child that she will not have the same schedule as it was too hard. D20 is fantastic at time management but during the second semester there were weeks where she got 8 hours of sleep over 5 days due to the amount of work. I would recommend dropping down to Honors for US history and keeping AP Lang. As a STEM kid, you should be fine with AP Calc BC and AP Chem. Keep the AP Spanish if it is easy for you.