Does anyone know if you are taking a high school make-up credit course in the summer (2 weeks;55 hours), as your final mark, do they add your summer school average and your other semester average and divide it by two? Or do they just take the higher mark or dock a certain percentage off? I'm in grade 11 by the way...

"McMaster currently accepts upgraded or repeated high school courses the same as first-attempt grades. The highest mark attained in the course will be used in the admission calculation. "

Source:
http://mcmasteru.intelliresp onse.c...s%3F &id=2397

McMaster only takes your highest grade. So if you took calculus and got in it a 70% the first time and an 86% the second time, they will only take the highest one (which is the 86 in this case) in calculating your admission average.
Also, mac doesn't care if you take the course summer school or night school.