I was taught calculus during my last two years of high school from a starting point of the conic sections (parabolas, elipses etc). Basically what you said dra

I was taught calculus during my last two years of high school from a starting point of the conic sections (parabolas, elipses etc). Basically what you said drawing of tangent lines etc. Limits and the fundamental theorem came after this. We used old school TI graphics calculators in the classroom. This was 15+ years ago so students today probably have better tools available (In Australia some schools give laptops to students nowso at least something like excel is available) we certainly had better then pencil and paper in the late 90's. My first year university calculus course covered 2 years of high school math in about 5 weeks and moved on to things like Taylor series Laplace transforms etc. There were people who hadn't studied calculus at high school in the lectures but they were the minority. I'd imagine if this was their first exposure it would have been a struggle.