i would work my butt off at your dad's place only because you don't pay taxes on that. i would quit the other.
i would work on the scholarships at night or when you have free time when you aren't working for your dad.
i would sock away all your money you got and all the money you make by working for your dad into something safe, like a CD or tax free bond or something that will grow with not too much risk.
get a loan for your law school that is interest free until you graduate. Let your money grow in your CD's and "safe" mutual funds in the meantime. That's about 2 years or so.
when you graduate, pay off any outstanding loans your scholarships can't cover. because you never know, you might end up with no loans at all, because you may get merit scholarships on the way.
then you also saved up all your money building interest. put that money down on a house while working as a lawyer, marry, have 2 kids, and a dog. you're all set.