['I am going to ace all of my classes this semester.', "That's awesome!  I know that took a lot of hard work!", "I didn't overload myself like last time so I know I will."]
That's the best way to go about it - make sure you have time for all the things you need time for.  That way you're not running around like a chicken with your head cut off.
I am going to ace all my classes this semester. I am determined.