Calculus Online Summer School

I’m taking advanced functions (12) in grade 11 because I took grade 11 functions in grade 10 second semester. I am thinking of taking calculus and vectors online over the summer in grade 11 as I’ll be finished advanced functions. My mark will almost certainly be better online and it will be finished in a month. Is there any reason I shouldn’t take it online? Will universities disregard the mark if it is done in online summer school? Is having no math courses senior year a bad idea, even if I took 5 math courses throughout high school?