Is it okay to take AP Calc A/B without taking Calc (H) or Calc (Regular)? Would it be harder to keep up?
Calculus AB is normally taken in the year after completing precalculus. Why would your high school want you to take an even less rigorous calculus course before taking calculus AB?
The path to Calculus from precalculus to Calculus is to take either AP Calc AB or AP Calc BC, or in many schools now, AP Calc AB and then AP Calc BC without a choice. Some schools also offer Honors Calc, which you could go into, but then you won’t be able to take another Calc class (ie AP Calc AB) after that, at least in HS.
Do schools even offer regular Calculus?
Some high schools offer a calculus course that is less rigorous than calculus AB. It may be modeled on college calculus for business majors courses (but there is obviously no AP or other credit or advanced placement available in college).
IB high schools offer math SL (standard level) courses that include an introduction to calculus, though not enough for colleges to give subject credit or advanced placement for the exam score. Some high schools add enough material for IB math SL students to also take the AP calculus AB exam for subject credit or advanced placement.
Our school does Pre-Cal then you can choose AB or BC. There is nothing in between.
The school itself sets the path pathway. But in almost every case, the prereq for Calc AB is precalc. Whether precalc honors is needed versus regular depends on how the math department flows the topics; many honors precalc courses start the first few chapters of Calc AB in the last quarter.
So unless there’s something very unusual about your HS, a full calc course is not needed first.
Not uncommon at larger high schools.
In DD’s school, the highest math track takes Trigonometry/Calculus A one year and Calculus BC the next. The next track down takes precalculus then Calculus AB. Her high school also offers a non honors calculus class. A humanities student could take that in lieu of AB, or a STEM hopeful on the college prep track could take it to boost their chances at a STEM program at directional colleges or their equivalents.
Yes, in our HS students go from pre-calc to either Honors Calc, Calc A/B, or Calc B/C.
I suggest you talk to your math teacher and/or guidance counselor to understand how the math sequence works at your particular HS.