MBP.
Before anyone says otherwise, I do think an iPad can function great as both a consumption and production device, but that doesn't change the fact that — as a standalone solution — a MBP can do a whole lot more right now, and you'll be better off with it for school.
Among other things, you might sign up for a class that uses software that doesn't run on an iPad. Without a secondary computer besides the iPad, your options for back-up are far more limited than with a MBP. Unless you'll have another Mac or PC around anyway, a MBP makes more sense.