Calculus.

Start calc 3 in july...I think this will be the first math class i've taken where I will actually have to try in.

Calc 3 was the easiest, personally. Once you have the fundamentals of 1&2 down, 3 is expansion into multivariable, with more vectors.
 


Honestly, four days and I learned Calc from this guy. Obviously I busted my ass, but a four day commitment and his videos is all it takes!

Yup, between this guy and another guy with a YouTube video I covered all of my calc ii stuff (up to about Lagrange and Simpson approximation, double integrals, etc.) in 2 days. Not bad at all.